Estimating error +50/-20% question

[Cos]

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[killramos]

Can you back it up with historical overruns / savings for each step compared to initial cost estimate?

[Cos]

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[bjstare]

Originally posted by killramos
Can you back it up with historical overruns / savings for each step compared to initial cost estimate?

This is not what he's looking for.


@OP: You're talking about a "Class 4 Estimate", just google that and you'll come up with lots of stuff. :thumbsup:

EDIT: I decided to do it for you. This should help:

http://imgur.com/auY0g3n.jpg

EDIT @: I can't get the damn pic to show up, but if you click the link it goes there anyways.

[FraserB]

Try looking up AACE RP No. 18R-97 Cost Estimate Classification System - As Applied in Engineering, Procurement and Construction for the Process Industries.

Should be a good place to start. Or PM your email and I'll send the Powerpoint I have.

[killramos]

Interesting, sounds pretty specific to your area of business though.

What do you do again? Might help others who are in more similar boats provide advice.

[Cos]

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[riander5]

Typical facilities engineering estimates

CJblair pretty much nailed it

[ExtraSlow]

I have some experience with this as well. While there are published standards or goals for each class of estimates, a lot of larger organizations also tend to modify them for internal use based on historical accuracy, or more often, internal political factors.

Worked somewhere that had an accepted early estimate standard of +100% / -50%. It's sole purpose was to discourage the use of "first pass" early estimates and to encourage project managers to do a better job at scoping to get themselves to the next level.

[FraserB]

Lost your work email Cos.

The presentation I can send is the source for CJ's picture.

[Cos]

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[Cos]

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[suntan]

This also works for penis size.