Software Engineering - Old Questions

3. Define the COCOMO model with example.

The COCOMO (Constructive Cost Model) is one of the most popularly used software cost estimation models i.e. it estimates or predicts the effort required for the project, total project cost and scheduled time for the project. This model depends on the number of lines of code for software product development.

COCOMO model has three types:

1. The Basic COCOMO

It is the one type of static model to estimates software development effort quickly and roughly. It mainly deals with the number of lines of code and the level of estimation accuracy is less as we don’t consider the all parameters belongs to the project. The estimated effort and scheduled time for the project are given by the relation:

Effort (E) = a*(KLOC)b  MM

Scheduled Time (D) = c*(E)d  Months(M)

Where,

• E = Total effort required for the project in Man-Months (MM).
• D = Total time required for project development in Months (M).
• KLOC = the size of the code for the project in Kilo lines of code.
• a, b, c, d = The constant parameters for a software project.

2. The Intermediate COCOMO

The intermediate model estimates software development effort in terms of size of the program and other related cost drivers parameters (product parameter, hardware parameter, resource parameter, and project parameter) of the project. The estimated effort and scheduled time are given by the relationship:

Effort (E) = a*(KLOC)b *EAF  MM
Scheduled Time (D) = c*(E)d  Months(M)

EAF = It is an Effort Adjustment Factor, which is calculated by multiplying the parameter values of different cost driver parameters. For ideal, the value is 1.

3. The Detailed COCOMO

It is the advanced model that estimates the software development effort like Intermediate COCOMO in each stage of the software development life cycle process.