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From: shilling@pinto.gatech.edu (John Shilling)
Newsgroups: comp.software-eng
Subject: Re: Using COCOMO to estimate development schedules
Message-ID: <18252@gatech.edu>
Date: 28 Mar 89 12:37:23 GMT
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Sender: news@gatech.edu
Reply-To: shilling@pinto.UUCP (John Shilling)
Organization: School of Information and Computer Science / Georgia Tech
Lines: 24

I have two questions about COCOMO

1.  Isn't the accuracy of the model limited by an initial guess of
    DELIVERED lines of source code?  Is there any reason to believe that
    a guess of delivered lines of source code is any more accurate than
    simply guessing at the resources required directly?  And just what is a 
    line     of source code anyway?  Seriously.  Is it delineated by a newline
    character?  Is it the number of statements?  Does it include comments?

2.  In what I have seen on the COCOMO model the weights on the factors 
    are given to two significant digits past the decimal point.  This raises 
    all sorts of flags with me.  Back in numerical analysis I learned not to 
    represent digits     that were below the level of accuracy of the 
    computation.  Given     the level of uncertainty in the evaluation of 
    the factors, I have a     hard time believing that the computations are 
    accurate to two decimal digits (it has to be more than crunching numbers, 
    it has to mean something).  Does anyone out there have evidence to the
    contrary?


John J. Shilling
School of Information & Computer Science, Georgia Tech, Atlanta GA 30332
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