1. FUNCTION POINT ANALYSIS & ESTIMATION
Gurpreet Singh
M.Tech CSE Part Time – 3rd Semester
Roll No. 17 & Regd. No

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3. What is Function Point Analysis (FPA)?
It is designed to estimate and measure the time, and thereby the cost, of developing new software applications and maintaining existing software applications.
It is also useful in comparing and highlighting opportunities for productivity improvements in software development.
It was developed by A.J. Albrecht of the IBM Corporation in the early 1980s.
The main other approach used for measuring the size, and therefore the time required, of software project is lines of code (LOC) – which has a number of inherent problems.
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4. The Function Point Methodology
Five key components are
identified based on logical user view
Inputs
Outputs
Inquiries
Internal Logical Files
External Interface Files
Input
Inquiry
Output
Internal
Logical
Files
Application
External
Interface
File
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6. The Function Point Methodology
14 Optional General Systems Characteristics are evaluated and used
to compute a Value Adjustment Factor (VAF)
General System Characteristics
Data Communication On-Line Update
Distributed Data Processing Complex Processing
Performance Objectives Reusability
Heavily Used Configuration Conversion & Install Ease
Transaction Rate Operational Ease
On-Line Data Entry Multiple-Site Use
End-User Efficiency Facilitate Change
The final calculation is based upon the Unadjusted FP count X VAF
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8. What is Function Point Analysis (FPA)?
These function-point counts are then weighed (multiplied) by their degree of complexity:
Simple Average Complex
Inputs
Outputs
Files
Inquires
Interfaces
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9. What is Function Point Analysis (FPA)?
A simple example:
inputs
3 simple X 2 = 6
4 average X 4 = 16
1 complex X 6 = 6
outputs
6 average X 5 = 30
2 complex X 7 = 14
files
5 complex X 15 = 75
inquiries
8 average X 4 = 32
interfaces
3 average X 7 = 21
4 complex X 10 = 40
Unadjusted function points
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10. What is Function Point Analysis (FPA)?
Continuing our example . . .
Complex internal processing = 3
Code to be reusable = 2
High performance = 4
Multiple sites = 3
Distributed processing = 5
Project adjustment factor = 17
Adjustment calculation:
Adjusted FP = Unadjusted FP X [ (adjustment factor X 0.01)]
= X [ ( X 0.01)]
= X [0.82]
= Adjusted function points
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14. FUNCTION POINT ANALYSIS
Project Estimation
DEFINITION
CAPABILITY
ESTIMATE
PROJECT
SIZE
PROJECT
COMPLEXITY
RISK
FACTORS
REQUIREMENT
discuss estimating, the issue of sizing vs. estimating
the issue is that I did more work, not that I delivered more functionality
your estimating model has to account for the more work that comes with increased complexity X X
Schedule
Costs
Effort
FUNCTION POINT ANALYSIS
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19. Conclusions Project Management can be successful
Requirements can be managed
Projects can be sized
Performance can be successfully estimated
Process improvement can be modeled
Measurement can be accomplished
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20. Thanks
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