COCOMO cost drivers

The initial estimates made in the COCOMO II model are adjusted using a set of attributes (project cost drivers) that reflect:

1.Product characteristics such as the required system reliability and product complexity.

2.Computer characteristics such as execution time or memory constraints. These are constraints imposed on the software by the hardware platform.

3.Personnel characteristics such as programming language skills that take the experience and capabilities of the people working on the project into account.

4.Project characteristics of the software development project such as the IDE that is available and the development schedule.

The following table shows all 17 of the project cost drivers that may be taken into consideration.

Attribute Type Description
RELY Product Required system reliability
CPLX Product Complexity of system modules
DOCU Product Extent of documentation required
DATA Product Size of database used
RUSE Product Required percentage of reusable components
TIME Computer Execution time constraint
PVOL Computer Volatility of development platform
STOR Computer Memory constraints
ACAP Personnel Capability of project analysts
PCON Personnel Personnel continuity
PCAP Personnel Programmer capability
PEXP Personnel Programmer experience in project domain
AEXP Personnel Analyst experience in project domain
LTEX Personnel Language and tool experience
TOOL Project Use of software tools
SCED Project Development schedule compression
SITE Project Extent of multisite working and quality of inter-site communications

Example of use of the COCOMO 2 model