Evaluating the impact of process improvements quantitatively using process modeling

The concept of continuous process improvement, although familiar in the manufacturing arena, is just starting to be implemented in the software industry. Currently, software development organizations have identified potential process improvements and are working to implement results from ISO 9000 audits and Capability Maturity Model (CMM) Software Process Assessments. Quantitative methods are needed to prioritize process changes and to justify resources for proposed improvements based on overall process performance. However, these methods have not yet been developed.This work uses software process modeling to predict the impact of potential process changes on quantitative performance measures before a substantial commitment of time and resources is made. The work addresses the performance measures of development cost, source code quality, and project schedule. This analysis can be used to prioritize process improvements based on their potential performance impact and to obtain management support for the proposed change.The proposed modeling approach is applied to a realistic example process and potential process change with assumed task durations and outcomes. This example process and potential process change are analyzed using a stochastic simulation approach which was developed by Marc Kellner et al. at SEI using the STATEMATE modeling tool.