Confused in "analogous estimating" method
I'm confused in the "Analogous estimating" method
in PMBOK 4th version, page 171 states that "analogous estimating uses the value of parameters, such as scope, cost, budget, and duration or measures of scale such as size, weight, and complexity, from a previous, similar project as the basis for estimating the same parameter or measure for a current project."
1. From the definition, it's very much we need to use the actual historical data for it. However, in Rita's book 6th edition, question 5, page 250, the choice "Analogous estimating use historical data" is not a correct choice.
2. in my experience, I usually use Analogous estimating as bottom-up approach, but not sure why it seems PMBOK promote this method as "top-down", which I feel quite unconfortable and don't know how what to call the estimating way that I'm doing so far (as I also try to use the same term that PMI promote)
Any advise on this?
Thanks
Binh
dohaboy79
Wed, 11/10/2010 - 08:13
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1- Parametric estimation is
1- Parametric estimation is the one that uses Historical data, not Analogous estimation.
2- Analogous estimating is always a High level estimation (Top-Down) & not a detailed bottom-up.
bpp9614
Wed, 11/10/2010 - 15:19
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Analogous Estimation
Hi Binh,
Analogus is for sure uses historical data. However, rita's question was little twisted and she used the word
"Detailed Actual Historical Data" . We never use the detailed actual data as it is. It always gives you a rough estimation.
We use that as a reference and new
estimation is based on it. It always uses TOP-DOWN approach. Get the big whole data and then
break it down and go step by step down, till you get it detailed enough.
-Bish
PMzilla_binh
Thu, 11/11/2010 - 06:29
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Thanks Bish and all, I'm
Thanks Bish and all, I'm clear now!
pmalik
Sat, 07/09/2016 - 10:39
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Analogous vs parametiric
Hi,
You can read this article http://www.pmbypm.com/analogous-parametric-estimation/ to understand the difference with examples.
BR.