Constructive Cost Model [B. Boehm]
Hierarchy of COCOMO models (parameters)
–basic: prg size
–intermediate: prg size & cost drivers
–advanced: prg size & cost drivers per phase
Cost Drivers: Team Capability, Product Complexity, Reliability, Problem Domain Experience, Development practices, Tools, Language Experience, etc.
Parameters
- number and complexity of functions
- number and complexity of modules
- number of lines of code
- number and duration of steps in your development process
- skills and technologies involved
Basic Relation
- person-month / nbr-of-people = duration
- example:
–36 person-month, 1 developer, 36 month
–36 person-month, 2 people, 18 month
–36 person-month, 12 people, 3 month
Project Types
organic mode:
–relatively small and simple
–small team of skilled developers
small size, little innovation, relax deadline, stable environment
semi-detached:
–intermediate in size and complexity
–mixed skill levels on the team
Medium size, Medium innovation, Medium deadline, Medium environment
embedded:
–hard constraints for HW, SW, operation
large size, Greater innovation, Tight deadline, Complex environment like hardware and interface
COCOMO 2 models
- Application composition model. Used when software is composed from existing parts.
- Early design model. Used when requirements are available but design has not yet started.
- Reuse model. Used to compute the effort of integrating reusable components.
- Post-architecture model. Used once the system architecture has been designed and more information about the system is available.
