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

2. 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
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3. Workshop Topics COCOMO III Model Overview
Discuss issues with COCOMO III Cost Drivers
Cost driver definition refinement
The New “Nominal”
10/20/2016
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4. 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
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5. 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
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6. 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
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7. 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
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8. 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
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9. 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
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10. 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
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11. Example of a shift in Nominal (N) rating Use of Software Tools (Tool)
In this example, High (H) is the new Nominal (N)
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12. 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
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13. 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? Make suggestions and be a model reviewer!
10/20/2016
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