COCOMO III Workshop Summary Brad Clark 31tst International Forum on COCOMO and System/Software Cost Modeling October 20, 2016

The COCOMO III Project COCOMO® (COnstructure COst MOdel) is the most widely used, free, open source software cost estimation model in the world. But also Most widely referenced Most widely validated And Most widely rebutted 10/20/2016 Copyright © USC-CSSE

Workshop Topics COCOMO III Model Overview Discuss issues with COCOMO III Cost Drivers Cost driver definition refinement The New “Nominal” 10/20/2016 Copyright © USC-CSSE

COCOMO III Project Purpose The purpose of the project presents a huge challenge Broaden audiences of COCOMO® and address scope of modern projects: mobile devices, web/internet, big data, cloud-targeted, and multi-tenant software Every parameter of COOCMO III has to defined and rated so as to be interpreted across different audiences, i.e., from Military to Information System projects Each domain has different constraints, practices, and terminology 10/20/2016 Copyright © USC-CSSE

Required Software Security (SECU) There are multiple security evaluation criteria: Banking, FDA, HIPPA, DoD, SEI Should the definition include threat? Malicious hackers Foreign governments Should the definition address exposure On the network Under guard, separated from outside environment Should the definition include descriptors such as: Confidentiality Integrity Availability Still working to make this a cross-domain cost driver 10/20/2016 Copyright © USC-CSSE

Platform Constraints (PLAT) This driver has a number of characteristics: Execution time constraint Primary/Secondary storage constraint Communication bandwidth constraint Power constraint Different domains have different constraint Not all can be listed Solution is to collapse this driver to one characteristic For any domain, what is the single highest constraint that has to be addressed during development / maintenance? But what it there are multiple high constraints? 10/20/2016 Copyright © USC-CSSE

Platform Volatility (PVOL) This driver had two characteristics: Targeted platform rate of change Concurrent development for the target platform and software application The issue was with the 2nd characteristic about how to define it for multiple domains There was discussion with replacing concurrent development with Technology Readiness Levels Decision was made to drop the 2nd characteristic 10/20/2016 Copyright © USC-CSSE

Tester Capability – New There is Analyst Capability and Programmer Capability cost driver Should there be a Test Capability cost driver based on: Test design Test plan development Capability in test execution Documentation No new driver: this is accounted for in the Impact of Software Failure (FAIL) driver 10/20/2016 Copyright © USC-CSSE

The New “Nominal” Study of productivity trends over the past 40 years reveals a shift in “nominal” ratings The shift in the nominal rating was shown graphically for seven (7) drivers For each driver, we discussed the definition for a new “nominal” 10/20/2016 Copyright © USC-CSSE

Impact of Productivity Trends Kendall's Rank Correlation Coefficients between the Completion Year and COCOMO II Cost Drivers (sorted by degrees of correlation) Cost driver Kendall’s τ p-value TOOL Use of Software Tools -0.37 2.20E-16 PMAT Process Maturity (now PCUS) -0.30 1.22E-13 STOR Main Storage Constraint (now PLAT) -0.29 1.31E-11 TIME Execution Time Constraint (now PLAT) -0.26 6.62E-10 PLEX Platform Experience -0.17 1.98E-05 PVOL Platform Volatility -0.18 2.04E-05 APEX Applications Experience 0.17 4.88E-05 LTEX Language and Tool Experience -0.15 2.84E-04 DATA Database Size 0.13 1.81E-03 RELY Required Software Reliability -0.10 1.42E-02 CPLX Product Complexity 1.58E-02 PREC Precedentedness of Application -0.09 2.13E-02 ACAP Analyst Capability 0.08 4.87E-02 10/20/2016 Copyright © USC-CSSE

Example of a shift in Nominal (N) rating Use of Software Tools (Tool) In this example, High (H) is the new Nominal (N) 10/20/2016 Copyright © USC-CSSE

New Issue: How does higher quality (less rework) reduce effort? Schedule Model Schedule (Months) Software product size estimate Staffing Levels Software product, platform, personal & project attributes Effort Model Effort (Person Months) Costs ($$) Labor Rates Number of est. non-trivial defects for Requirements, Design, & Code Defect Introduction Model Number of est. residual defects and the residual defect density Defect removal profile levels Defect Removal Model 10/20/2016 Copyright © USC-CSSE

Invitation to Participate CSSE invites you to collaborate on model development Review model formulation Submit data for model calibration Actual Size Effort Schedule Defects Model Parameters Review of COCOMO III model If you contribute data for model calibration, you will receive: An advanced copy of the new model Comparison of your data with respect to other data points used to calibrate the model Please talk with me afterwards if you are interested Want to Participate? www.cocomo3.com JASanche@usc.edu Make suggestions and be a model reviewer! 10/20/2016 Copyright © USC-CSSE