Path: utzoo!utgpu!attcan!uunet!ncrlnk!emdeng!tmcclory
From: tmcclory@emdeng.Dayton.NCR.COM (Thomas.J.Tom.McClory)
Newsgroups: comp.software-eng
Subject: Project Sizing and Estimating
Keywords: Software Engineering Planning Estimating
Message-ID: <551@emdeng.Dayton.NCR.COM>
Date: 5 Oct 88 16:59:39 GMT
Organization: E&M Dayton, NCR Corporation, Dayton, Ohio
Lines: 44


As a newly minted manager, I've suddenly developed an
interest in effort estimating and project sizing techniqes.
What I need are techiques that can be used to produce
"accurate" size and error estimates early in the software
life-cycle (usually with only a vague idea of what the
requirements are), and for predicting the risk of 
estimate error (i.e. Mr. General Manager, there is a 50%
likelyhood the optimistic assumptions made in this estimate
will actually occur). "Accurate" means making delivery within 20%
either side of the estimated date. 

Some of the methods I've read about, but not used are:

	COCOMO		Barry Boehm
	SLIM		Larry Putnam
	SPQR-20		Capers Jones

I'm sure there are others.  How well do any of these
techniques work?  My shop primarily produces systems
software to be sold to (hopefully) many commercial customers.  
Development cycles are always "aggressive".  Quality is always a
concern.  A model that shows the trade-offs between 
schedule/effort/quality/complexity would really be nice.

Since I'm experimenting, I don't want to spend gobs of
money buying some black box model, unless I see rave reviews
from netland.  The COCOMO model is public domain, has
anyone got a public domain implementation I could get a hold of?
Are there any other public domain models I can try?  Any
good references on sizing and project estimating I should read?  

There has to be a better way than finger to the wind
estimates followed by prayer!
----------------------------------------------------------------------
Tom McClory			   | UUCP: tmcclory@emdeng.dayton.ncr.com
NCR Corporation	EMD-4	 	   | 
Engineering & Manufacturing Dayton |
Dayton, OH. 45479		   |
-- 
Tom McClory			   | UUCP: tmcclory@emdeng.dayton.ncr.com
NCR Corporation	EMD-4	 	   | or ...gatech!hubcap!ncrcae!ncrlnk!emdeng
Engineering & Manufacturing Dayton |
Dayton, OH. 45479		   |