Adapting, correcting, and perfecting software estimates: a maintenance metaphor

A hybrid continuous software estimation model supporting adaptive, corrective, and perfective estimation activities is described. The adaptive activity accommodates new system or user requirements or reflects new organizational realities. Corrective maintenance remedies an error detected in the software product, and perfective maintenance eliminates processing inefficiencies and enhances performance of the overall software system. An implementation using constructive cost model (Cocomo) and the system dynamics (SD) simulator is presented. Three examples are presented that demonstrate how the model can be used: before the project starts to adapt the Cocomo estimates to organizational realities, during software development to correct initial assumptions about sizing, and after project completion to perfect model estimates.<
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