Combatting Use Case Points’ Limitations with COCOMO(R) II and Relative Difficulty

Software cost estimates become more accurate as more information becomes available, but are needed early for business case analyses, bids, and resource management. Use Case Points satisfy the ability to make software size estimates early in the lifecycle because they only require understanding how an actor will use the system. Though Use Case Points are easy to calculate, they might over-simplify a project's size and lead to inaccurate estimates. The Use Case Points method has also been heavily criticized for its technical and environmental factors, since they were not calibrated and verified with data. COCOMO(R) II possesses a rich knowledge base of factors that were calibrated and verified with data and expert judgment. Calculating and calibrating an effort model on Unified Code Count (UCC)'s project set using COCOMO(R) II's parameters and Use Case Points needed an additional relative difficulty factor for greatly improved effort estimates.