DTU ProjectLab - User contributions [en-gb]

File:Bottom-up-estimating.png

2021-02-28T07:34:49Z

OliVittrup: OliVittrup uploaded a new version of "File:Bottom-up-estimating.png"

Top-down vs bottom-up estimations

2021-02-28T07:31:06Z

OliVittrup:

'' Written by Oliver K. Vittrup ''

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way of getting a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation process is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described. 
 
'''Single-point estimate''' 
This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>. A visual example of the single-point estimation technique can be seen from the following figure.

[[File:One-Point-Estimate.png|700px|thumb|center|Example of a 'Single-point estimation'. Inspired by figure found at https://project-management.info/analogous-estimating/]]
 
'''Ratio estimate''' 
A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators would believe that the new project would take 130% of the reference project, which increases the cost, duration and need for resources following this ratio.<ref name="projectmanagementinfo2"/>. 
 
'''Estimate range''' 
An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/> A visual example of the estimate range can be seen from the following figure.
[[File:Estimation-range.png|700px|thumb|center|Example of an 'Estimate range'. Inspired by figure found at https://project-management.info/analogous-estimating/]]
 

'''Three-point estimate''' 
This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.<ref name="projectmanagementinfo2"/>

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 
The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed. An example of this can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Inspired by figure found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

*'''project-management.info''' offers a broad palette of information within the field of project management. It also offers a more detailed description of the tools described in this article. The articles on project-management.info also shows the tool in a visual manner, which makes the theory easier to understand and use.
*'''apm.org.uk''' is the official site of the Association for Project Management. They describe their goal as "''Inspiring communities to deliver meaningful change for societal benefit by advancing the art, science, theory and practice of project management.''"
*'''pmstudycircle.com''' is a website made from a student, frustrated about the missing information about project management available on the web, when he was writing his exam. Here he has gathered a lot of relevant information about project management.

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-27T11:06:53Z

OliVittrup:

'' Written by Oliver K. Vittrup ''

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described. 
 
'''Single-point estimate''' 
This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>. A visual example of the single-point estimation technique can be seen from the following figure.

[[File:One-Point-Estimate.png|700px|thumb|center|Example of a 'Single-point estimation'. Inspired by figure found at https://project-management.info/analogous-estimating/]]
 
'''Ratio estimate''' 
A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators, would believe that the new project would take 130% of the reference project.<ref name="projectmanagementinfo2"/>. A visual example of the ratio estimation technique can be seen from the following figure. 
 
'''Estimate range''' 
An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/>
[[File:Estimation-range.png|700px|thumb|center|Example of an 'Estimate range'. Inspired by figure found at https://project-management.info/analogous-estimating/]]
 

'''Three-point estimate''' 
This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.<ref name="projectmanagementinfo2"/>

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 
The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed. An example of this can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Inspired by figure found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

*'''project-management.info''' offers a broad palette of information within the field of project management. It also offers a more detailed description of the tools described in this article. The articles on project-management.info also shows the tool in a visual manner, which makes the theory easier to understand and use.
*'''apm.org.uk''' is the official site of the Association for Project Management. They describe their goal as "''Inspiring communities to deliver meaningful change for societal benefit by advancing the art, science, theory and practice of project management.''"
*'''pmstudycircle.com''' is a website made from a student, frustrated about the missing information about project management available on the web, when he was writing his exam. Here he has gathered a lot of relevant information about project management.

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-27T10:58:01Z

OliVittrup:

'' Written by Oliver K. Vittrup ''

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed. An example of this can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Inspired by figure found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described. 
 
'''Single-point estimate''' 
This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>. A visual example of the single-point estimation technique can be seen from the following figure.

[[File:One-Point-Estimate.png|700px|thumb|center|Example of a 'Single-point estimation'. Inspired by figure found at https://project-management.info/analogous-estimating/]]
 
'''Ratio estimate''' 
A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators, would believe that the new project would take 130% of the reference project.<ref name="projectmanagementinfo2"/>. A visual example of the ratio estimation technique can be seen from the following figure. 
 
'''Estimate range''' 
An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/>
[[File:Estimation-range.png|700px|thumb|center|Example of an 'Estimate range'. Inspired by figure found at https://project-management.info/analogous-estimating/]]
 

'''Three-point estimate''' 
This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.<ref name="projectmanagementinfo2"/>

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

*'''project-management.info''' offers a broad palette of information within the field of project management. It also offers a more detailed description of the tools described in this article. The articles on project-management.info also shows the tool in a visual manner, which makes the theory easier to understand and use.
*'''apm.org.uk''' is the official site of the Association for Project Management. They describe their goal as "''Inspiring communities to deliver meaningful change for societal benefit by advancing the art, science, theory and practice of project management.''"
*'''pmstudycircle.com''' is a website made from a student, frustrated about the missing information about project management available on the web, when he was writing his exam. Here he has gathered a lot of relevant information about project management.

== References ==
<references />

File:Estimation-range.png

2021-02-27T10:55:31Z

OliVittrup:

File:One-Point-Estimate.png

2021-02-27T10:54:45Z

OliVittrup: OliVittrup uploaded a new version of "File:One-Point-Estimate.png"

Top-down vs bottom-up estimations

2021-02-27T10:29:59Z

OliVittrup:

'' Written by Oliver K. Vittrup ''

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed. An example of this can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Inspired by figure found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described

'''Single-point estimate'''
This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>

[[File:One-Point-Estimate.png|800px|thumb|center|Example of a 'Single-point estimation'. Inspired by figure found at https://project-management.info/analogous-estimating/]]

* Ratio estimate
** A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators, would believe that the new project would take 130% of the reference project.<ref name="projectmanagementinfo2"/>
* Estimate range
** An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/>
* Three-point estimate
** This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.<ref name="projectmanagementinfo2"/>

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

*'''project-management.info''' offers a broad palette of information within the field of project management. It also offers a more detailed description of the tools described in this article. The articles on project-management.info also shows the tool in a visual manner, which makes the theory easier to understand and use.
*'''apm.org.uk''' is the official site of the Association for Project Management. They describe their goal as "''Inspiring communities to deliver meaningful change for societal benefit by advancing the art, science, theory and practice of project management.''"
*'''pmstudycircle.com''' is a website made from a student, frustrated about the missing information about project management available on the web, when he was writing his exam. Here he has gathered a lot of relevant information about project management.

== References ==
<references />

File:One-Point-Estimate.png

2021-02-27T10:27:15Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-27T10:15:15Z

OliVittrup:

'' Written by Oliver K. Vittrup ''

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed. An example of this can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Inspired by figure found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described

* Single-point estimate
** This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>
* Ratio estimate
** A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators, would believe that the new project would take 130% of the reference project.<ref name="projectmanagementinfo2"/>
* Estimate range
** An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/>
* Three-point estimate
** This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.<ref name="projectmanagementinfo2"/>

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

*'''project-management.info''' offers a broad palette of information within the field of project management. It also offers a more detailed description of the tools described in this article. The articles on project-management.info also shows the tool in a visual manner, which makes the theory easier to understand and use.
*'''apm.org.uk''' is the official site of the Association for Project Management. They describe their goal as "''Inspiring communities to deliver meaningful change for societal benefit by advancing the art, science, theory and practice of project management.''"
*'''pmstudycircle.com''' is a website made from a student, frustrated about the missing information about project management available on the web, when he was writing his exam. Here he has gathered a lot of relevant information about project management.

== References ==
<references />

File:Bottom-up-estimating.png

2021-02-27T10:11:43Z

OliVittrup: OliVittrup uploaded a new version of "File:Bottom-up-estimating.png"

Top-down vs bottom-up estimations

2021-02-26T13:04:04Z

OliVittrup:

'' Written by Oliver K. Vittrup ''

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described

* Single-point estimate
** This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>
* Ratio estimate
** A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators, would believe that the new project would take 130% of the reference project.<ref name="projectmanagementinfo2"/>
* Estimate range
** An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/>
* Three-point estimate
** This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.<ref name="projectmanagementinfo2"/>

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

*'''project-management.info''' offers a broad palette of information within the field of project management. It also offers a more detailed description of the tools described in this article. The articles on project-management.info also shows the tool in a visual manner, which makes the theory easier to understand and use.
*'''apm.org.uk''' is the official site of the Association for Project Management. They describe their goal as "''Inspiring communities to deliver meaningful change for societal benefit by advancing the art, science, theory and practice of project management.''"
*'''pmstudycircle.com''' is a website made from a student, frustrated about the missing information about project management available on the web, when he was writing his exam. Here he has gathered a lot of relevant information about project management.

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-26T08:41:25Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described

* Single-point estimate
** This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>
* Ratio estimate
** A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators, would believe that the new project would take 130% of the reference project.<ref name="projectmanagementinfo2"/>
* Estimate range
** An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/>
* Three-point estimate
** This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.<ref name="projectmanagementinfo2"/>

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

*'''project-management.info''' offers a broad palette of information within the field of project management. It also offers a more detailed description of the tools described in this article. The articles on project-management.info also shows the tool in a visual manner, which makes the theory easier to understand and use.
*'''apm.org.uk''' is the official site of the Association for Project Management. They describe their goal as "''Inspiring communities to deliver meaningful change for societal benefit by advancing the art, science, theory and practice of project management.''"
*'''pmstudycircle.com''' is a website made from a student, frustrated about the missing information about project management available on the web, when he was writing his exam. Here he has gathered a lot of relevant information about project management.

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-25T19:40:10Z

OliVittrup: /* Annotated Bibliography */

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described

* Single-point estimate
** This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>
* Ratio estimate
** A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators, would believe that the new project would take 130% of the reference project.<ref name="projectmanagementinfo2"/>
* Estimate range
** An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/>
* Three-point estimate
** This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

*'''project-management.info''' offers a broad palette of information within the field of project management. It also offers a more detailed description of the tools described in this article. The articles on project-management.info also shows the tool in a visual manner, which makes the theory easier to understand and use.
*'''apm.org.uk''' is the official site of the Association for Project Management. They describe their goal as "''Inspiring communities to deliver meaningful change for societal benefit by advancing the art, science, theory and practice of project management.''"
*'''pmstudycircle.com''' is a website made from a student, frustrated about the missing information about project management available on the web, when he was writing his exam. Here he has gathered a lot of relevant information about project management.

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-25T19:39:00Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described

* Single-point estimate
** This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>
* Ratio estimate
** A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators, would believe that the new project would take 130% of the reference project.<ref name="projectmanagementinfo2"/>
* Estimate range
** An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/>
* Three-point estimate
** This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

*'''project-management.info''' offers a broad palette of information within the field of project management. It also offers a more detailed description of the tools described in this article.
*'''apm.org.uk''' is the official site of the Association for Project Management. They describe their goal as "''Inspiring communities to deliver meaningful change for societal benefit by advancing the art, science, theory and practice of project management.''"
*'''pmstudycircle.com''' is a website made from a student, frustrated about the missing information about project management available on the web, when he was writing his exam. Here he has gathered a lot of relevant information about project management.

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-25T19:23:43Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

The top-down estimating can be used as a starting point for the bottom-up estimate. This gives a quick introduction to the project, which if needed, can be analyzed further. The technique works best and gives the most reliable estimates, when the project is similar to an earlier finished project, and the assumptions regarding the similarities is correct.<ref name="projectmanagementinfo2"/> As mentioned earlier, the top-down estimation can be performed in four different ways, which will be briefly described

* Single-point estimate
** This technique within the top-down estimation, defines the way of estimating the project from the most similar project performed earlier. Therefore, the project is analyzed and compared to projects in the same category as itself, and then estimated on the background of the most similar one. If the reference project cost 500.000 DKK, the top-down estimate for the new project would then be similar equal to 500.000 DKK.<ref name="projectmanagementinfo2"/>
* Ratio estimate
** A ratio estimate compares the new project to a reference project with enough similarities. The two projects are then compared in regards to size, which gives a ratio between them. As an example, the project estimators, would believe that the new project would take 130% of the reference project.<ref name="projectmanagementinfo2"/>
* Estimate range
** An estimate range shows the price range between a series of earlier performed projects similar to the new project planned. The estimate range is then going from the cheapest project up to the most expensive. The estimate range would often be made with a 'most likely'-estimate.<ref name="projectmanagementinfo2"/>
* Three-point estimate
** This approach requires the project manager to make three estimates, which includes an optimistic estimate, a pessimistic estimate and a most likely estimate. They are then to be converted into a final estimate.

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

'''Project-management.info'''

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-25T17:53:13Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways. <ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021].</ref> 
An example of a bottom-up estimating process can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Can be found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-25T16:56:17Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways<ref name="project-management.info2">:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project.<ref name="projectmanagementinfo1"> Sebastian. Bottom Up Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021] </ref> 
An example of a bottom-up estimating process can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Can be found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="projectmanagementinfo1"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.<ref name="projectmanagementinfo2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below.<ref name="projectmanagementinfo1"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-25T16:34:51Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> Rowland, M. 2019. Three ways to approach cost estimation. [online] Available at: https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ [Accessed February 18th 2021].</ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study">
Bugajenko, O. Top-Down & Bottom-Up Estimating Techniques in Project Management. [online] Available at: https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html [Accessed February 18th 2021].</ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> Usmani, F. 2020. 4 Tools to Estimate Costs in the Project Management. [online] Available at: https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ [Accessed February 18th 2021]</ref>

Top-down estimating can be done in four different ways<ref name="project-management.info2">:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="project-management.info"> Sebastian. Bottom-Up Estimating. Definition, Example, Pros & Cons. [online] Available at: https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ [Accessed February 18th 2021]</ref> 
An example of a bottom-up estimating process can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Can be found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="project-management.info"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below. <ref name="project-management.info2"> Sebastian. Analogous Estimating. Definition, Examples, Pros & Cons. [online] Available at: https://project-management.info/analogous-estimating/ [Accessed February 18th 2021]</ref>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below. <ref name="project-management.info"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-23T09:17:27Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ </ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study"> https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html </ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ </ref>

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="project-management.info"> https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ </ref> 
An example of a bottom-up estimating process can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Can be found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

Top-down estimating can be done in four different ways:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="project-management.info"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below. <ref name="project-management.info2"> https://project-management.info/analogous-estimating/ </ref>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below. <ref name="project-management.info"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-23T07:00:31Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ </ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study"> https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html </ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ </ref>

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="project-management.info"> https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ </ref> 
An example of a bottom-up estimating process can be seen from the following figure.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Can be found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

Top-down estimating can be done in four different ways:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="project-management.info"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below. <ref name="project-management.info"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below. <ref name="project-management.info"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-21T13:48:24Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ </ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study"> https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html </ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ </ref>

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="project-management.info"> https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ </ref> 
An example of a bottom-up estimating process can be seen.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Can be found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

Top-down estimating can be done in four different ways:
* a single-point estimate
* a ratio estimate
* an estimate range
* a three-point estimate

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="project-management.info"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below. <ref name="project-management.info"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below. <ref name="project-management.info"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-21T12:01:29Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ </ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study"> https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html </ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ </ref>

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="project-management.info"> https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ </ref> 
An example of a bottom-up estimating process can be seen.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Can be found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="project-management.info"/> This is differentiated from company to company. 

== Limitations ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below. <ref name="project-management.info"/>

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

The main limitations, or consequences, which is present when using the bottom-down estimating technique, is listed below. <ref name="project-management.info"/>

* The bottom-up estimation technique is expensive to do, both in regards to effort and time, and from this resources needed for the process.
* The estimation regarding the cost of the project relies on the estimated time frames, which is then relying on the estimated resources needed for the project. From this, the estimation could be incorrect, if error occurs in one of these estimates.
* If the project is at a large scale, the estimates made with the bottom-up estimation could be ignoring the possibility of integration efforts in regards to the listed project tasks.
* When put into work, it is sometimes seen, that the estimating can be

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-21T11:04:48Z

OliVittrup:

== Abstract ==
When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames. It is important to get the project off to a good start, given that success of the project depends on the estimation - both in regards to time and cost. When estimating (or in other words 'predicting the future'), the project manager can use the following methods:

- Top-down estimating 
- Bottom-up estimating

By choosing the top-down approach, the project manager chooses to make an overall scope of the project. From here, the major elements of the project is being listed and estimated separately. This approach creates a rough idea of the project size and the different timeframes of the project elements. The advantages of using the top-down approach is less time consuming and requires a limited amount effort. The estimates created by this method often turns out larger than the ones, which has been found using the bottom-up approach. <ref name="apm"> https://www.apm.org.uk/blog/three-ways-to-approach-cost-estimation/ </ref> 
The bottom-up approach is on the other hand a very time-consuming and costly method, but it gives a more accurate estimate of the project time and cost. By using the bottom-up approach, the cost and time frame is being calculated for every activity related to the project. The values and time frames are then aggregated in order to estimate the total cost and project time. <ref name="PMI-Project"> Project Management: A guide to the Project Management Body of Knowledge (PMBOK guide), 6th Edition (2017) </ref> The bottom-up approach is often used in order to gain stakeholders to buy in on the project.

== Big idea ==

The term 'estimating' in terms of project management can be defined as "''the process of predicting the cost and time needed to deliver project products''". <ref name="study"> https://study.com/academy/lesson/top-down-bottom-up-estimating-techniques-in-project-management.html </ref> The estimation part is an important step on the way to a get a good product, which satisfies the costumer and/or the user, when it is delivered in the end. The estimation proces is used in order to predict the cost and the duration of a given project, which is making it possible to make the decisions, which will benefit the project. When estimating, it is also possible to make a decision regarding the viability of the project, when the financial requirements has been determined. 
The duration of a project is important to know in regards to costumer expectations and in order to know when the product can be delivered. From the estimation process, the project manager can use the determined time frames for time scheduling, which is relevant informations for interested stakeholders. During the project, the project manager can hold the real time data up against the estimated values in order to monitor the performance of the project. <ref name="study"/> 
Project estimations can be a fast task, but it can also be very time consuming. This all comes down to how the project manager wishes to prioritize the estimation, and is a decision on whether the time used on estimating is worth the effort in the end. The estimation process can be carried out by using top-down estimating as well as the bottom-up estimating.

==== Top-down estimating ====

Top-down estimating, also refered to as analogous estimating, defines the way of estimating based on the information which is available about the project at the moment. The tool often uses similar projects as guide lines in regards to tasks, cost and project durations. The top-down approach is a fast and efficient way of estimating, but can leave out information, which is unique to the particular project, and the result can therefore be different from the real price and duration. <ref name="pmstudy"> https://pmstudycircle.com/2012/06/4-tools-to-estimate-costs-in-the-project-management/ </ref>

==== Bottom-up estimating ====

The bottom-up estimating approach is to be used, when a detailed estimate is needed for the project. By using the bottom-up estimation, the project cost and duration is estimated on a task specific level, allowing the project manager to plan each and every task. The task costs and durations can then be aggregated in the end, which will result in a very detailed project estimate. This approach also makes it possible to estimate the amount of resources needed for the project. <ref name="project-management.info"> https://project-management.info/bottom-up-estimating-definition-example-pros-cons/ </ref> 
An example of a bottom-up estimating process can be seen.

[[File:Bottom-up-estimating.png|800px|thumb|center|Example of bottom-up estimating. Can be found at https://project-management.info/bottom-up-estimating-definition-example-pros-cons/]]

The bottom-up estimating is performed at the lowest level with-in the 'Work breakdown structure', which is where all of the activities within a given project has been named and listed.

The big differences between the to estimation techniques is that the top-down estimating can be used for any level of of the project phase, even when information may be limited. On the other hand, it is fairly common that the bottom-up approach is used, when a lot of knowledge has been obtained about the project.

== Application ==

The two different tools used for estimation purposes can be used in different times of the project phase.

==== Top-down estimating ====

The top-down estimating strategy can be put into work when
* the project has a limited amount of information available
* the project manager wants a fast and cheap estimation of the project cost and duration
* the project manager needs to see the big picture and an accurate estimate is not needed

==== Bottom-up estimating ====

The bottom-up estimating can be used for estimating
* the needed time for the project (aggregated task durations)
* the resources needed for the project
* the project cost

The bottom-up estimating technique should be put into work when the project is in a place, where it needs accurate predictions regarding future. This can be, as shown in the bulletpoints, in regards to duration, cost and resources. 
The different estimates can also depend on each other. The task duration will often depend on the resources, which has been assigned to the specific task. The cost is estimated from the time- and resource estimates by multiplying them with the price per unit.<ref name="project-management.info"/> This is differentiated from company to company. 

== Limitations -
''critically reflect on the tool/concept/theory and its application context. What can it do, what can it not do? Under what circumstances should it be used, and when not? How does it compare to the “status quo” of the standards – is it part of it, or does it extent them? Discuss your article in the context of key readings / resources provided in class. Substantiate your claims with literature'' ==

The two different estimation techniques each have their limitations, when being used for cost- and duration estimations. These will be listed below:

==== Top-down estimating ====

The main limitations, or consequences, which is present when using the top-down estimating technique, is listed below.

* The use of the top-down estimation gives a rough and not quite accurate picture of the project.
* When comparing the current project to an earlier finished reference project, the assumptions regarding similarities between them has to be correct. If the assumptions were wrong, the determined estimate would then be useless for the project.
* The potential inaccuracy in regards to the results, makes it harder to make decisions and project planning based on the estimates found from using the top-down approach.

==== Bottom-up estimating ====

== Annotated Bibliography ==

''Provide key references (3-10), where a reader can find additional information on the subject. The article MUST make appropriate references to the and reference material provided in class – either incorporating it as a source, or critically discussing aspects that are missing from it but covered by this article. Summarize and outline the relevance of each reference to the topic (around 100 words per reference). The bibliography is not counted in the suggested 3000 word target length of the article.''

== References ==
<references />

Top-down vs bottom-up estimations

2021-02-20T14:20:29Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-20T14:10:43Z

OliVittrup:

File:Bottom-up-estimating.png

2021-02-20T13:47:33Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-20T13:09:45Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-19T15:44:50Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-19T14:05:39Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-19T12:17:29Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-19T11:23:24Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-19T11:22:46Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-19T11:20:40Z

OliVittrup: /* Big idea - describe the tool, concept or theory and explain its purpose. The section should reflect the current state of the art on the topic */

Top-down vs bottom-up estimations

2021-02-19T11:07:40Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-19T09:30:25Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-18T19:57:32Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-18T17:36:05Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-18T17:19:37Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-18T15:13:37Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-16T11:06:12Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-16T11:00:37Z

OliVittrup:

Top-down vs bottom-up estimations

2021-02-12T12:33:16Z

OliVittrup:

Articles Spring Term 2021

2021-02-12T12:28:45Z

OliVittrup:

=Overview of 2021 Wiki Collections=

{| class="wikitable sortable"
|+Spring Term 2021 Wiki Collections
|Group name
|First name
|Surname
|Student number
|[[Article name]]
|-
|-
|TAs Example
|Thomas
|Giannoulopoulos
|s192419
|[[APPM Example 2021]]
|-
|-
|Group 12
|Christian
|Frøsig
|s175044
|[[Belbin's 9 team roles]]
|-
|-
|Group 1
|Oliver
|K. Vittrup
|s163754
|[[Top-down vs bottom-up estimations]]
|-
|-
|44
|Jeyad
|M. Baig
|s153585
|[[Task Management - 3 Levels of Planning Methods]]
|-
|-
|Group 17
|Quoc-Khanh Rose-Marie Therese
|Madsen
|s123462
|[[Applying Tuckman’s model for team development]]
|-
|-
|31
|Haoxiang
|Sang
|s192258
|[[Cost control with statistic tools]]
|-
|-
|Not yet
|He
|Fan
|s192195
|[[Work Break Down Structure]]
|-
|-
|Group 19
|Ángel
|Castro del Olmo
|s193246
|[[Stakeholder Engagement and Sustainability in Maritime Spatial Planning]]
|-
|-
|44
|Abdullah Shams
|Turkmani
|s153337
|[[ICT Agreement]]
|-
|-
|Group 17
|Jacopo
|Renzi
|s210445
|[[Double Diamond Model]]
|-
|-
|Group 35
|Helga Sigríður
|Magnúsdóttir
|s202027
|[[Network Planning]]
|-
|-
|12
|Cæcilie
|Kortbæk
|163873
|[[Double diamond]]
|-
|-
|Group 18
|Frithjof Johannes
|Thiem
|s202972
|[[DevOps]]
|-
|-
|12
|Emilie
|Winther Schmidt
|163884
|[[Iron Triangle]]
|-
|-
|12
|Anna
|Fredgaard
|s163887
|[[Active Listening Technique]]
|-
|-
|35
|Ruben
|Raes
|s202029
|[[Iron Triangle of Project Management]]
|-
|-
|21
|Claudia
|Balcells
|s202939
|[[APPPM Issue Tree]]
|-
|-
|35
|Brynja
|Gudmundsdottir
|s202030
|[[FAST goals]]
|-
|-
|16
|Andrea
|Pin Morales
|s205567
|[[The Business Case]]
|-
|-
|16
|Lena Maria
|Thyen
|s202969
|[[The 7 Habits of Highly Effective People]]
|-
|-
|35
|Úlfar
|Viktorsson
|s202022
|[[The 4 Disciplines of Execution]]
|-
|-
|16
|Moritz
|Rindermann
|s202976
|[[Tuckmans model for Team Development]]
|-
|-
|Group 29
|Heiðdís Ósk
|Pétursdóttir
|s202025
|[[Efficiency and Effectiveness]]
|-
|-
|31
|Xabier
|Martínez de Zabarte
|s210323
|[[Scrumban]]
|-
|-
|17
|Aldís Braga
|Eiríksdóttir
|s202045
|[[Blake-Mouton Managerial Grid]]
|-
|-
|32
|Jan Otis
| Ernst
|s210433
|[[RACI Matrix]]
|-
|-
|3
|Julie
| Finne-Ipsen
|s153987
|[[Kahneman - Two Thinking Systems]]
|-
|-
|24
|Maria Eileen
| Hubbuck
|s210444
|[[Risk Management-Identification]]
|-
|-
|11
|Alina
| Barun
|s202514
|[[Maslow's Hierarchy of Needs]]
|-
|-
|24
|Felix Vinzenz
|Wütherich
|s202968
|[[Emotional Intelligence and Leadership]]
|-
|-
|28
|Ariadna
|Ramos
|s191852
|[[The Work Breakdown Structure (WBS)]]
|-
|-
|Group 27
|Jakob
|Grønvald
|s164346
|[[Maslow‘s Hierarchy of Needs, Motivation in the workplace]]
|-
|-
|Group 16
|Martina
|Rampazzo
|s202895
|[[Scientific management]]
|-
|-
|Group 2
|John
|Fritz
|s202967
|[[Learning plan]]
|-
|-
|Group 24
|Henning
|Duwe
|s210450
|[[SWOT Analysis]]
|-
|-
|Group 14
|Søren Emil
|Kjær
|s201528
|[[GANTT]]
|-
|-
|Group 23
|Mathilde Kremmer
|Broberg
|s175074
|[[Corrective and Preventive Actions (CAPA)]]
|-
|-
|Group 14
|Rune Lykke
|Høg
|s165012
|[[The use of the A3 management process]]
|-
|-
|Group 35
|Tinna Hrönn
|Unudóttir
|s202032
|[[Constructive communication]]
|-
|-
|Group 17
|Eva Rún
|Arnarsdóttir
|s203214
|[[Biases in Project Management]]
|-
|-
|Group 24
|Astrid
|Skovhus
|s164499
|[[Getting Things Done (GTD)]]
|-
|-
|Group 7
|Phillip
|Dyrberg
|s164503
|[[Double diamond: A design process model]]
|-
|-
|Group 14
|Amanda Emilie
|Søborg Berthelsen
|s154707
|[[The Johari Window]]
|-
|-
|Group 23
|Nicolai Mossing
|Madsen
|s164515
|[[SMART Goals (Specific, Measurable, Attainable, Relevant, Time-bound)]]
|-
|-
|Group 27
|Marie-Louise Wolfsberg
|Schmidt
|s164417
|[[The Affect Heuristic]]
|-
|-
|Group 4
|Erika Marie
|Strøm
|s203224
|[[Parkinson’s Law]]
|-
|-
|Group 16
|Beatrice
|Ranzato
|s202887
|[[X-Matrix Hoshin Kanri]]
|-
|-
|Group 9
|Helene Waldmann
|Jørgensen
|s173891
|[[Lag & Lead]]
|-
|-
|Group 4
|Zahra
|Al-Mosawi
|s193938
|[[Project Communications Management]]
|-
|-
|Group 14
|William Axel Linderoth
|Michaelen
|s153275
|[[Design-Build]]
|-
|-
|Group 31
|Jesús
|Gracia Yoldi
|s210111
|[[Kanban in APPPM]]
|-
|-
|Group 35
|Katrín Erla
|Bergsveinsdóttir
|s202026
|[[Contingency plans]]
|-
|-
|Group 1
|Cecilie Marie Raagaard
|Christensen
|s160832
|[[Work breakdown structure (WBS)]]
|-
|-
|Group 19
|Ali Jamal
|Jomeh
|s173741
|[[SMART goals: A project management tool]]
|-
|-
|Group 15
|Tobias
|Hyldmo
|s206658
|[[High performing teams]]
|-
|-
|Group 5
|Samah
|Said
|s203228
|[[Business Process Excellence (BPEX)]]
|-
|-
|Group 3
|Emilie
|Torp
|s153320
|[[Goal Hierarchy]]
|-
|-
|Group 3
|Victor Nørregaard
|Schwærter
|s164745
|[[Milestone Planning]]
|-
|-
|Group 9
|Jacob
|Ammitsøe
|s173849
|[[Self-Awareness]]
|-
|-
|Group 18
|Anna
|Bjørn Reland
|s154556
|[[Choosing the appropriate medium (oral – written – hybrids)]]
|-
|-
|Group 10
|Wail
|Atrari
|s170706
|[[The Double Diamond Tool: Prevent budget overruns and delays in your projects]]
|-
|Group 10
|Helená Evin
|Cinar
|s164741
|[[SWOT Analysis Management]]
|-
|-
|Group 10
|Mohammad
|Abou Hassan
|s160101
|[[Implementing SWOT]]
|-
|-
|Group 10
|Ahmet
|Akgül
|s152597
|[[Smart goals (Specific, Measurable, Achievable, Realistic, and Timely)]]
|-
|-
|Group 2
|Amalie
|N. Müller
|s173675
|[[Big five personality traits (OCEAN model)]]
|-
|-
|Group 29
|Pétursdóttir
|Stefanía Ósk
|s202044
|[[Management vs leadership qualities]]
|-
|-
|Group 10
|Abdulahi
|Hayle Hassan
|s164691
|[[Stakeholder management]]
|-
|-
|Group 27
|Louise
|Landschoff
|s165111
|[[SCRUM - A Project Management Framework]]
|-
|-
|Group 10
|Sara
|Alabiidi
|s164650
|[[The Blake-Mouton Managerial Grid]]
|-
|-
|Group 4
|Felix
|Dressel
|s202965
|[[SPALTEN]]
|-
|-
|Group 11
|Sandra
|Nielsen
|s153370
|[[Conflict ladder]]
|-
|-
|Group 11
|Lise Munch
|Nordheim
|s200400
|[[McGregor's X & Y theory]]
|-
|-
|Group 2
|Simon
|Knutsson
|s202041
|[[Earned Value Management (EVM)]]
|-
|-
|Group 12
|Christoffer
|Askgaard
|s165098
|[[Design the team you need to succeed using Belbin's team roles]]
|-
|-
|Group 24
|Gaute Bø
|Aaløkken
|s202065
|[[Cultural diversity in teams]]
|-
|-
|Group 2
|Lukas
|Tanzer
|s200120
|[[Continuous Improvement]]
|-
|-
|Group 7
|Sofie
|Lundsteen
|s170285
|[[Team roles at work]]
|-
|-
|Group 14
|Josefine
|M. Schuler
|s154055
|[[Applying the Hawthorne studies to project management]]
|-
|-
|Group 3
|Amalie Nordstrøm
|Nielsen
|s153272
|[[The seven characteristic principles]]
|-
|-
|Group 14
|Louise Damborg
|Frederiksen
|s185238
|[[Bias in a Team Setting]]
|-
|-
|Group 1
|Georg Holger
|Waage
|s163819
|[[Fishbone Diagram]]
|-
|-
|Group 28
|Özgenur
|Baştuğ
|s203033
|[[Variation Orders in Construction Projects]]
|-
|-
|Group 9
|Mads
|Møhlenberg
|s173879
|[[A hybrid consisting of Agile and Stage Gate]]
|-
|-
|Group 29
|Svanhvít Birta
|Guðmundsdóttir
|s203174
|[[Project Milestones]]
|-
|-
|Group 23
|Bente
|Meidahl Münsberg
|s175068
|[[Gantt Charts]]
|-
|-
|Group 27
|Frederik
|Carlsson
|s164345
|[[FAST Goals]]
|-
|-
|Group 11
|Tobias
|Rydahl
|s200471
|[[Using DISC assessment for project team management]]
|-
|-
|Group 7
|Mads
|Støjfer-Hønberg
|s174303
|[[SCRUM - An Agile Project Management Framework]]
|-
|-
|Group 21
|Matthieu
|Buy
|s202925
|[[The Five-Factor Model (OCEAN)]]
|-
|-
|Group 18
|Astrid Helene
|Erecius
|s171013
|[[Choosing communication media for negotiation]]
|-
|-
|Group 44
|Zainab
|Jalal
|s165491
|[[Work Breakdown Structure in project management]]
|-
|-
|Group 2
|Anna Felicia Mai
|Lindström
|s202046
|[[Project Status Reporting]]
|-
|-
|Group 28
|Alberto
|Melloni
|s202894
|[[Pre-mortem analysis]]
|-
|-
|Group 29
|Thore Uwe
|Aye
|s202746
|[[Quality Gates in Project Management]]
|-
|-
|Group 9
|Lydia
|Tsintzou
|s193745
|[[SWOT Analysis Guide]]
|-
|-
|Group 28
|Kendra Ana
|Rodríguez López
|s200182
|[[The big five (OCEAN)]]
|-
|-
|Group 4
|Christine
|Fryland
|s153875
|[[Theory X-Y]]
|-
|-
|Group 28
|Manas P.
|Dalvi
|s210143
|[[Effective Tools for Multiple Project Management]]

Top-down vs bottom-up estimations

2021-02-12T12:28:08Z

OliVittrup: Created page with "== Abstract == When starting a new project, an important task for the project manager, is the estimation process. This can both be an estimation regarding cost and time-frames..."

Articles Spring Term 2021

2021-02-09T09:29:02Z

OliVittrup: