Using statistical relationships (e.g., COCOMO II ) based on lines of code or function points. Enterprise/Repeat Work
Relative sizing (e.g., Fibonacci) based on complexity rather than hours. Active Agile Teams Software Estimation Best Practices, Tools & Tec...
Modern teams use a "layered" approach, applying different techniques as project clarity increases along the . Description Best Stage Analogy-Based Comparing the new project to a similar completed one. Early/Concept Three-Point (PERT) Using statistical relationships (e
Captures Optimistic, Most Likely, and Pessimistic estimates to find a weighted average: Planning/Risk Assessment not a single scalar.
Use the Estimate Accuracy Ratio (EAR) (Actual Hours / Estimated Hours). A healthy target is 0.9–1.1 . 3. Leading Estimation & Management Tools
Decomposing a system into granular tasks and summing individual estimates. Detailed Design
Every credible estimate is a range, not a single scalar. An "initial idea" estimate typically has a range of 0.25x to 4x , narrowing to ±10% only after a detailed technical spec is signed.