The document discusses various software estimation techniques including function point analysis, three point estimation, and COCOMO. It outlines the importance of estimation for budgeting, planning, and customer satisfaction. Different techniques are suited for different project stages and sizes. Function point analysis involves counting logical files, external inputs, external outputs, external queries, and other factors to estimate effort. Three magic formulae can also help estimate project duration, staffing needs, and minimum time. Metrics like effort slippage and percentage of efforts used help evaluate estimation accuracy.

1. Software Estimation Presented by – Dinesh Singh

2. Agenda Importance of Software Estimation Type of Estimation Estimation Tools/Techniques Which Technique to use and when Estimation Process Estimation Tips Explanation of Few Technique Estimation Metrics

3. Importance of Software Estimation Budgeting & Decision Making Forecast Profitability (IRR, NPV, Payback period, Benefit cost ratio , opportunity cost) Reliable Resource Planning & Scheduling Satisfied Customer Under Estimation lead to loss, over estimation may loose business Process Improvement Fuzzy estimates can only lead to fuzzy project plans

4. Type of Estimation ( Size, Efforts , Schedule and cost) Initiation (order of magnitude -25 to +75) Budgetary (Planning -10 to +25) Definitive ( Requirement -5 to +10) Intermediate Post construction

5. Estimation Tools/Techniques Top Down Expert Judgment ( Experience & Historical data, Use Delphi method) Analogous ( On similar projects, Top down) Three point Analysis - (o+4m+p)/6 Reserve Analysis (Contingency, Management) Bottom UP Function Point Analysis Use Case Point Object Point Analysis Program Complexity Method COCOMO-Constructive Cost Model (Based on LOC)

6. Which Technique to use and when Function Point Analysis/Expert/ three point/reserve /Analogous System is to be developed from scratch Scope is available at broad level only Person with high project management experience Use Case Point / Object Point / PCM / Base sizing Functionality is clear up to screen level Enhancement of existing system Scope is very clear Person with good technical knowledge

7. Estimation Process Collect Initial Requirement Estimate Size Estimate Efforts Produce Schedule Approve Estimate Develop Product Approved Actual Analyse Estimation Process Historical Project Data Resource Availability

8. Tips Create Details Work Break down structure till manageable level Spend enough time to do proper Estimate Involve Developer Use more than one people and technique to estimate separately ( for large projects) Use at least one estimation tool Mine historical information to tune your estimation capability Mention Dependencies and assumptions

9. Function Point Analysis (FPA) FPA ILF ( Logical Entity resides on internal system) e.g Customer Details EIF ( External Entity referred by system) EI ( User interaction screen , it may have ILF) EQ ( Queries , does not update ILF or EIF) EO (Across Application eg XML, can update ILF &EIF) RET ( Normalization of the ILF & EIF) DET ( User recognized data element type) FTR ( Files used in transitions)

10. Function Point Analysis (FPA) ILF Function point EIF Function point 15 15 10 6 + RETs 15 10 7 2 - 5 RETs 10 7 7 1 RET 51+ DETs 20 - 50 DETs 1-19 DETs 10 10 7 6 + RETs 10 7 5 2 - 5 RETs 7 5 5 1 RET 51+ DETs 20 - 50 DETs 1-19 DETs

11. Function Point Analysis (FPA) EI Function point 6 6 4 3 + FTRs 6 4 3 2 FTRs 4 3 3 1 FTR 16 + DETs 5 -15 DETs 1- 4 DETs

12. Function Point Analysis (FPA) EO Function point 7 7 5 4 + FTRs 7 5 4 2 - 3 FTRs 5 4 4 1 FTR 20+ DETs 6- 19 DETs 1-5 DETs

13. Function Point Analysis (FPA) EQ Function point 6 6 4 4 + FTRs 6 4 3 2 - 3 FTRs 4 3 3 1 FTR 20+ DETs 6-19 DETs 1-5 DETs

14. Function Point Analysis (FPA) Function point calculation UFPC = Total of all function points Degree of Influence on 14 points (Response time, transaction rate, ..) VAF = 0.65 + (TDI *0.01) Function point = UFPC * VAF Efforts Estimate 3 GL - 0.5 to 1 FP/day 4 GL - 1 to 1.5 FP/day 5 GL - 2 to 5 FP/day

15. FPA Template OPE Template Exercise & Demo

16. Three Magic formulae Three Magic formulae Project Duration = 2.5 * (Cube Root of Work Months) Optimum Staffing Size = Square Root of Work Months Minimum Duration = 0.75 * (Cube Root of Work Months)

17. Estimation Metrics Effort Slippage- ( Actual – Planned)*100/Planned % Efforts used - Actual*100/Planned or budgeted % Rework efforts- Rework*100 / Total %Review & testing – Review & testing *100/ Total

18. Q & A

19. Thanks