QA estimation based on Capers Jones

[Livewire]

Ok I need help. I just started work at a new company - so far I never had problems with software quality assurance estimation. But this company uses a very strange 40% on top of the entire project estimation (architecture, design and coding) formula - supposed to be based on the book form Capers Jones.

So for a project that is estimated to run for 250 man-days they would estimate 100 man days on top for QA! But if I have a project that uses only 60 MD's for coding how can that be accurate?

Does anyone know the Book from Capers Jones and what it really says?

I might just have to read the entire thing - but it would be helpful to know what other PM's think about this.

Thank you for your comments in advance!

[pmkb]

Haven't read the book, but I do have a question... Does the 250 day estimate include time for QA/testing? Seems like you could be doubling up on the QA estimate easily if the basis for the estimate isn't perfectly clear.