Cost estimation models for reuse and prototype SW development life-cycles

Abstract

The Cocomo cost estimation model was developed to estimate the cost of developing software utilizing the waterfall life-cycle model. The assumptions in the waterfall model account for many software development situations, but do not account for the actual development process when the requirements are known to be unstable or incomplete or when extensive code and design information are reused. The prototype and reuse life-cycle models, respectively, were developed to model these specific situations. The assumptions made by any life-cycle model directly influence its cost estimation model; therefore, when the life-cycle model is inappropriate, its cost estimation model is also inappropriate. This makes the Cocomo cost estimation model inadequate for estimating development effort for software developed utilizing the prototype or reuse software development life-cycle models. Two cost estimation models, one for the prototype software life-cycle model and one for the reuse software life-cycle model, are presented. Each cost estimation model is derived from the basic Cocomo model and modified to fit the characteristics of its respective life-cycle model.