• COCOMO model stands for a constructive cost model.
  • It was introduced by BERRY BOEHM in 1981.
  • COCOMO model is one of the most widely used software estimation models in the world.
  • COCOMO model is an order of three models:-
  1.  Basic COCOMO model
  2.  Intermediate COCOMO model
  3.  Advanced COCOMO model

According to COCOMO, there are three important classes of the software product are:-

  • Organic projects:-

This simple project is developed by a small team of experienced programmers in a familiar environment.

  • Semidetached:-

In this median teamwork on this project of mixed experience programmers.

  • Embedded projects:-

This software project must be developed within a set of tight hardware, software, and operational constraints.

1.  Basic COCOMO model

  • Approximate estimation of project parameters ( cost, time, effort, number of people).
  • Software development is estimated using LOC (line of code).
Effort applied ( E ) = a ( KLOC )b
Development time ( D ) = c(E)d

People required (  P ) = E/D

Project
a
b
c
d
Organic
2.4
1.05
2.5
0.38
Semidetached
3
1.12
2.5
0.35
Embedded
3.6
1.2
2.5
0.32

ADVANTAGE OF BASIC COCOMO MODEL:-

  • The basic COCOMO model is good for a quick, early, rough order-of-magnitude estimates of a software project.

2.  Intermediate COCOMO model 

  • It is an advance of the basic COCOMO model.
  • It refines obtained by the basic COCOMO model.
Effort applied ( E ) = a ( KLOC )b * EAF
Development time ( D ) = c(E)d

People required (  P ) = E/D

Project
a
b
c
d
Organic
3.2
1.05
2.5
0.38
Semidetached
3
1.12
2.5
0.35
Embedded
2.8
1.2
2.5
0.32

ADVANTAGE OF INTERMEDIATE MODEL:- 

  • This model is applied to most of the whole software system merchandise for straightforward associate degreed rough value estimation throughout an early stage.
  • It also can be applied at the merchandise element level for getting additional correct value estimation.

3.  Advanced COCOMO model/Detailed COCOMO model


In advanced/detailed COCOMO model complete software is divided into phases and then applying the COCOMO model to each phase cost and effort is calculate and then later all the sums are added.
 The phase is:-
  1. Planning
  2. System design
  3. Detailed design
  4. Phase cost 
  5. Integration
  6. Cost constructive model 

ADVANTAGE OF ADVANCED COCOMO MODEL:-

  • This model uses an endeavor multiplier factor for every section of the project. These section-dependent effort multipliers yield higher estimation as a result of the value driver ratings is also totally different throughout every phase.
  • This model gives a three-level product hierarchy and has other capabilities like a procedure for adjusting the section distribution of the event schedule.