Detailed COCOMO Model Uses same equations for estimation

• Uses, same equations for estimation, as the intermediate model • But detailed

• Four phases used in – detailed cocomo model are – 1. Requirement

The effort multipliers for detailed COCOMO are • Using these detailed cost drivers, •

Example 1 • Consider a project to develop a full screen editor. • The

System design Detail design Module code and test Integration and test Effort 0. 16

• Solution • Size in KLOC can be – 1. Screen edit =

• The formula for effort calculation is • E = Ai * (KLOC)

• Duration for completion of project can be calculated using following formula •

• 1. 2. 3. 4. Effort and schedule estimation for different phases System

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Detailed COCOMO Model

• Uses, same equations for estimation, as the intermediate model • But detailed model can estimate – the effort (E), duration & persons (P) • Of each of development phases, subsystems, modules

• Four phases used in – detailed cocomo model are – 1. Requirement Planning & Product Design (RPD) 2. Detailed Design (DD) 3. Code & Unit Test 4. Integrate & Test

The effort multipliers for detailed COCOMO are • Using these detailed cost drivers, • an estimate is determined for each phase of the lifecycle Phases Very Low Nominal High Very High RPD 1. 8 0. 85 1 0. 75 0. 55 DD 1. 35 0. 85 1 0. 9 0. 75 CUT 1. 35 0. 85 1 0. 9 0. 75 IT 1. 5 1. 2 1 0. 85 0. 7

Example 1 • Consider a project to develop a full screen editor. • The major components identified are 1. Screen edit 2. Command language interpreter 3. File input and output 4. Cursor movement 5. Screen movement The sizes estimated are 4 K, 2 K, 1 K, 2 K and 3 K delivered source lines of code. Use COCOMO model, to determine Overall cost and schedule estimates, assume effort adjustment factor (EAF) being 1. 21

System design Detail design Module code and test Integration and test Effort 0. 16 0. 26 0. 42 0. 16 Time 0. 19 0. 24 0. 39 0. 18

• Solution • Size in KLOC can be – 1. Screen edit = 4 KLOC 2. Command language interpreter = 2 KLOC 3. Final input & output = 1 KLOC 4. Cursor movement = 2 KLOC 5. Screen movement = 3 KLOC ------------------------Total = 12 KLOC

• The formula for effort calculation is • E = Ai * (KLOC) ^ Bi * EAF person – months • For organic project • Ai = 3. 2 and Bi = 1. o 5 • EAF is given as 1. 21 • E = 3. 2 * (12) ^ 1. 05 * 1. 21 • = 43. 48 * 1. 21 • = 52. 61 person - months

• Duration for completion of project can be calculated using following formula • D = Cb * (E) ^ Db months • Cb = 2. 5 and Db = 0. 38 • D = 2. 5 * (52. 61) ^ 0. 38 • = 11. 27 months

• 1. 2. 3. 4. Effort and schedule estimation for different phases System design = 0. 16 * 25. 61 = 8. 41 PM Detail design = 0. 26 * 52. 61 = 13. 67 PM Module code and test = 0. 42 * 52. 61 = 22. 09 PM Integration and test = 0. 16 * 52. 61 = 8. 41 PM Schedule estimation – 1. System design = 0. 19 * 11. 27 = 2. 14 months 2. Detail design = 0. 24 * 11. 27 = 2. 70 3. Module code and test = 0. 39 * 11. 27 = 4. 395 4. Integration and test = 0. 18 * 11. 27 = 2. 02