E-Cosmic: A Business Process Model Based Functional Size Estimation Approach

Software size is the key input for cost and effort estimation models. The effort and cost estimations as well as software size is needed at as early a phase of the project as possible. Conventional Early Functional Size Estimation methods enable predicting size at early phases but frequently variation of the results are high due to manual calculations and requirements of high degree of interpretation in situations where there is a lack of structured artifacts. On the other hand, automated Functional Size Measurement calculation approaches require constructs which are available in considerably late software development phases. In this study, an approach called e-Cosmic to overcome the reliability and subjectivity problems of early size estimation models is developed. As part of the approach a mapping between functional size measurement components of COSMIC FSM Method and common business process model constructs, was developed. The proposed method (e-Cosmic) is validated by three case studies. The result of the case studies has consistently showed less than 10% deviation with respect to the COSMIC FSM results. In addition, the automation of the estimation procedure eliminated measurer dependency and effort in conventional early functional size estimation methods.