1. Aim: Using COCOMO model to estimate efforts for given case study.
2. Objectives: From this experiment, the student will be able to for best effort estimation.
GET INSTANT HELP FROM EXPERTS!
- Looking for any kind of help on your academic work (essay, assignment, project)?
- Want us to review, proofread or tidy up your work?
- Want a helping hand so that you can focus on the more important tasks?
Hire us as project guide/assistant. Contact us for more information
Understand, identify, analyze To stress the importance of a good interface
design.
To understand the importance of software concepts in developing good
software
To motivate students to apply Software engineering fundamentals in their day
– to – day activities
3. Outcomes: The learner will be able to
Understand software concepts and design the problem related to software using related techniques.
4. Hardware / Software Required: Any text editor, Open source tool
5. Theory:
COCOMO is one of the most widely used software estimation models in the world. This model is developed in 1981 by Barry Boehm to give an estimate of the number of man-months it will take to develop a software product. COCOMO stands for “Constructive Cost Model”.
COCOMO has three different models that reflects the complexity-
● Basic model
● Intermediate model
● Detailed model
COCOMO applies to three classes of software projects:
1) Organic mode:
In this mode, relatively small, simple software projects with a small team are handled.
Such a team should have good application experience to less rigid requirements.
2) Semi-detached projects:
32
In this class an intermediate projects in which teams with mixed experience level are
handled .Such projects may have mix of rigid and less than rigid requirements.
3) Embedded projects:
In this class, projects with tight hardware, software and operational constraints are
handled.
1. Basic COCOMO computes software development effort (and cost) as a function of
program size. Program size is expressed in estimated thousands of source lines of
code (KLOC).
The basic COCOMO equations take the form
Effort Applied (E) = a
b (KLOC) b b [ person-months ]
Development Time (D) = c b (Effort Applied) d b [months]
People required (P) = Effort Applied / Development Time [count]
Where, KLOC is the estimated number of delivered lines (expressed in thousands) of
code for project.
2. Intermediate COCOMO computes software development effort as function of
program size and a set of “cost drivers” that include subjective assessment of product,
hardware, personnel and project attributes. This extension considers a set of four “cost
drivers”, each with a number of subsidiary attributes:-
• Product attributes
o Required software reliability
o Size of application database
o Complexity of the product
• Hardware attributes
o time performance constraints
o Memory constraints
o Volatility of the virtual machine environment
o Required turnabout time
• Personnel attributes
o Analyst capability
o Software engineering capability
o Applications experience
o Virtual machine experience
o Programming language experience
● Project attributes
33
o Use of software tools
o Application of software engineering methods
o Required development schedule
Each of the 15 attributes receives a rating on a six-point scale that ranges from “very
low” to “extra high” (in importance or value). An effort multiplier from the table
below applies to the rating. The product of all effort multipliers results in an effort
adjustment factor (EAF) . Typical values for EAF range from 0.9 to 1.4.
The Intermediate Cocomo formula now takes the form:
E= a i (KLoC) (b i
) (EAF)
Where E is the effort applied in person-year, KLoC is the estimated number of
thousands of delivered lines of code for the project, and EAF is the factor calculated
above. The coefficient a i and the exponent b i are given in the next table.
Software project a i b i
Organic 3.2 1.05
Semi-detached 3.0 1.12
Embedded 2.8 1.20
The Development time D calculation uses E in the same way as in the Basic COCOMO.
3. Detailed COCOMO incorporates all characteristics of the intermediate version with
an assessment of the cost driver’s impact on each step (analysis, design, etc.) of the
software engineering process.
The detailed model uses different effort multipliers for each cost driver attribute. These
Phase Sensitive effort multipliers are each to determine the amount of effort required to
complete each phase. In detailed cocomo,the whole software is divided in different
modules and then we apply COCOMO in different modules to estimate effort and then
sum the effort
In detailed COCOMO, the effort is calculated as function of program size and a set of
cost drivers given according to each phase of software life cycle.
A Detailed project schedule is never static.
The Six phases of detailed COCOMO are:-
● Plan and requirement.
● System design.
● Detailed design.
● Module code and test.
● Integration and test.
● Cost Constructive Model
6. Procedure:
34
Use appropriate model to respective case study for estimating efforts.
7. Conclusion:
● Basic COCOMO is good for quick, early, rough order of magnitude estimates of
software costs, but its accuracy is limited due to its lack of factors to account for
difference in project attributes (Cost Drivers). Intermediate COCOMO takes these
Cost Drivers into account and Detailed COCOMO additionally accounts for the
influence of individual project phases. In short COCOMO is better suited for
estimating modern software development of projects.
8. Viva Questions:
1. What are different types of COCOMO model?
2. Which model do u prefer for your case study?
9. Reference Books & Links
1. www.nptel.ac.in/courses/106105087/pdf/m11L28.pdf
2. https://files.ifi.uzh.ch/rerg/arvo/courses/seminar_ws02/…/Seminar_4.pdf
3. https://www.unf.edu/~broggio/cis6516/CocomoPresentation.ppt
4. ttps://sites.google.com/site/assignmentssolved/mca/semester5
StudyMumbai.com is an educational resource for students, parents, and teachers, with special focus on Mumbai. Our staff includes educators with several years of experience. Our mission is to simplify learning and to provide free education. Read more about us.
Leave a Reply
You must be logged in to post a comment.