Alexandra CossardProject Manager, PMP, Black Belt & ADKAR Practitioner| GSKRixensart, Belgium
Dear Community members,
Can someone tells me the way you decide to use one estimation technique rather than another one?
(i.e Why "Published Estimated data" and not "Analoguous Estimating" in the process "Estimate Activities Resource"? )
What is the rational behind?
Thanks in advance for your support,
Alex Saving Changes...
Sergio Luis ConteHelping to create solutions for everyone| Worldwide based OrganizationsBuenos Aires, Argentina
Usually I am not using some in the above list. Estimations,depend on two critical factors: Amount of information and time available to estimate. With that on hand you can select any method outside there. Saving Changes...
Alexandra CossardProject Manager, PMP, Black Belt & ADKAR Practitioner| GSKRixensart, Belgium
Thanks for your support Sergio. It make sense :)
Alex Saving Changes...
Senior Projects Manager | Field & Marten AssociatesNew Westminster, British Columbia, Canada
I do agree with Sergio, it always depends on what you have available and on the situation itself.
Definitely using Parametric Estimating is more accurate as it uses a relationship between variables (a unit cost/duration and the number of units) to develop the estimate.
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1 reply by Rajan Hariramabadran Varada
Nov 07, 2016 4:32 AM
Rajan Hariramabadran Varada
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Hi Alexandra,
I agree with Rami. Parametric Estimation has always worked for me.
More, I believe there should be appropriate consideration for the kind of team (competency and proficiency) that is involved in estimations.
As Sergio commented, it depends on accuracy requirement, time and information available. Analoguous estimating might be used when time is limited and accuracy is not that important in the initiating stage, I use all necessary information and tools and techniques when I prepare detailed estimation. Bottom up estimating is one of my favorite techniques in different processes for estimation, such as activity costs, resources etc.
By the way, analoguous or parametric estimating might not be used in Estimate Activity Resources process because the process of "Estimate Activity Resources" just needs to determine the type, quantity and level or grade of different resource for activities based on your project requirements, which means it doesn't require analysis of performance in historical records but may require expert judgement. Analoguous estimating might be used in Estimate Activity Duration and Costs, or even roughly in project level.
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1 reply by Alexandra Cossard
Nov 07, 2016 1:58 AM
Alexandra Cossard
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Hi Sungjoon.
I simply quoted that the T&T that are written in PMBoK. And sometines it is confusing so many techniques...
Thanks for your support !
Simple, you need to first determine the type of activity, and then the type of estimating to be used. Saving Changes...
Alexandra CossardProject Manager, PMP, Black Belt & ADKAR Practitioner| GSKRixensart, Belgium
Nov 06, 2016 6:13 PM
Replying to Sungjoon Park
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As Sergio commented, it depends on accuracy requirement, time and information available. Analoguous estimating might be used when time is limited and accuracy is not that important in the initiating stage, I use all necessary information and tools and techniques when I prepare detailed estimation. Bottom up estimating is one of my favorite techniques in different processes for estimation, such as activity costs, resources etc.
By the way, analoguous or parametric estimating might not be used in Estimate Activity Resources process because the process of "Estimate Activity Resources" just needs to determine the type, quantity and level or grade of different resource for activities based on your project requirements, which means it doesn't require analysis of performance in historical records but may require expert judgement. Analoguous estimating might be used in Estimate Activity Duration and Costs, or even roughly in project level.
Hi Sungjoon.
I simply quoted that the T&T that are written in PMBoK. And sometines it is confusing so many techniques...
Thanks for your support ! Saving Changes...
I do agree with Sergio, it always depends on what you have available and on the situation itself.
Definitely using Parametric Estimating is more accurate as it uses a relationship between variables (a unit cost/duration and the number of units) to develop the estimate.
Hi Alexandra,
I agree with Rami. Parametric Estimation has always worked for me.
More, I believe there should be appropriate consideration for the kind of team (competency and proficiency) that is involved in estimations. Saving Changes...
Celso Santos. Ph.D., PMPEngineer Project Manager| Virginia Department of TransportVirginia, United States
Hi Alexandra;
In my opinion it depends on how detailed you want it, usually in Construction we use bottom up estimate to give a detailed estimation and when we want know just about a basic estimation we can use parametric or analogous.
Best Saving Changes...
Ved SharmaStructural Engineer| The City of CalgaryCalgary, Alberta, Canada
It depends on the stage of your project. If you are in early stages at charter, you likely don't have much details available. At this time, you would likely make a high level estimate based on similar past projects experiences. As you move towards preliminary design, you will base your estimate on each scope item validated by conversations with industry to get a high level estimate. As you near detailed design, you will base your estimate on work packages and WBS with unit rates. At the time of Tender you will refine it further.
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1 reply by Alexandra Cossard
Nov 11, 2016 7:51 AM
Alexandra Cossard
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Thank you so much for your support ! It helps a lot .
Saving Changes...
Stéphane ParentSelf Employed / Semi-retired| Leader MakerPrince Edward Island, Canada
We typically estimate the input (i.e. time) directly, rather than estimate the output - lines of cod or functions points - for parametric converxion Saving Changes...
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