Post on 04-Jan-2016
COCOMOCOnstructive COst Model II
Copyright © 2007 Patrick McDermott
UC BerkeleyExtension
pmcdermott@msn.com
It’s a Name Game,Don’t Blame Boehm!
(rhymes)
Even if the numbers are not truly predictive, qualitative assessments are useful, and just pondering is a benefit.
Made up numbers can be surprisingly good!
Boehm& Friends
Boehm, Barry W., Chris Abts, A. Winsor Brown, Sunita Chulani, Bradford K. Clark, Ellis Horowitz, Ray Madachy, Donald J. Reifer & Bert Steece,Software Cost Estimation with COCOMO II,Upper Saddle River, New Jersey: Prentice Hall PTR (0-13-026692-2), 2000.
Center for Software EngineeringUniversity of Southern California
Simplified Formula
Multipliers SizeFactors
Multipliers Size 0.91 0.01 Factors
The Scale FactorsDriver Symbol VL Low Nominal High VH XHPREC Precedentedness 6.20 4.96 3.72 2.48 1.24 0.00FLEX Development flexibility 5.07 4.05 3.04 2.03 1.01 0.00RESL Architecture & risk 7.07 5.65 4.24 2.83 1.41 0.00TEAM Team cohesion 5.48 4.38 3.29 2.19 1.10 0.00PMAT Process maturity 7.80 6.24 4.68 3.12 1.56 0.00
Driver Factor Low Nominal HighPREC Precedentedness Largely Unprecedented Somewhat Unprecedented Generally FamiliarFLEX Development flexibility Occassional Relaxation Some Relaxation General ConformityRESL Architecture & risk Some Often GenerallyTEAM Team cohesion Some Difficult Interations Basically Cooperative Largely CooperativePMAT Process maturity CMM1 CMM 2 CMM 3
The Effort MultipliersDrivers Multiplier VL Low Nominal High VH XHRELY Required reliability 0.82 0.92 1.00 1.10 1.26DATA Database size 0.90 1.00 1.14 1.28CPLX Product complexity 0.73 0.87 1.00 1.17 1.34 1.74RUSE Developed for reusability 0.95 1.00 1.07 1.15 1.24DOCU Documentation match life cycle 0.81 0.91 1.00 1.11 1.23TIME Execution time constraint 1.00 1.11 1.29 1.63STOR Main storage constraint 1.00 1.05 1.17 1.46PVOL Platform volatility 0.87 1.00 1.15 1.30ACAP Analyst capability 1.42 1.19 1.00 0.85 0.71PCAP Programmer capability 1.34 1.15 1.00 0.88 0.76PCON Personnel continuity 1.29 1.12 1.00 0.90 0.81APEX Applications experience 1.22 1.10 1.00 0.88 0.81PLEX Platform experience 1.19 1.09 1.00 0.91 0.85LTEX Language & tool experience 1.20 1.09 1.00 0.91 0.84TOOL Use of software tools 1.17 1.09 1.00 0.90 0.78SITE Multisite development 1.22 1.09 1.00 0.93 0.86 0.80SCED Required development schedule 1.43 1.14 1.00 1.00 1.00
Examples
RUSE
Reusability
Low: None
Nominal: Across Project
High: Across Program
Very High: Across Product Line
Extra High: Across multiple Product Lines
PCON
Personnel Continuity
Very Low: 48% / Year
Low: 24% / Year
Nominal: 12% / Year
High: 6% / Year
Very High: 3% / Year