Solution

Methods for Cost & Effort Estimation

1. Expert Judgment / Delphi - Experts estimate, converge via iterations.
2. Analogy - Compare with similar past projects.
3. Decomposition:

• LOC-based / FP-based - Estimate size then use productivity
• Task-based - WBS tasks sum
  4. Empirical Models (Algorithmic):
• COCOMO (Basic, Intermediate, Detailed) - $Effort = a(KLOC)^b \\times EAF$
• COCOMO II - For modern lifecycle
• Putnam - Rayleigh curve, $Effort = L^3 / (C_k^3 t_d^4)$
• Halstead, Function Point
  5. Heuristic - Parkinson, Pricing to win

One Method in Detail - COCOMO Basic

Types: Organic ($a=2.4,b=1.05$), Semi-detached ($3.0,1.12$), Embedded ($3.6,1.20$) - Intermediate uses 15 cost drivers.

Steps:

1. Estimate KLOC
2. Apply $Effort = a(KLOC)^b$ (PM)
3. $Time = c(Effort)^d$ months
4. Cost = Effort × rate

Example: 30 KLOC Organic → $Effort=2.4×30^{1.05}=85 PM$, $Time=2.5×85^{0.38}=14$ months.

Used for planning, staffing and risk analysis.