Return on investment of software quality predictions

Software quality classification models can be used to target reliability enhancement efforts toward high risk modules. We summarize a generalized classification rule which we have proposed. Cost aspects of a software quality classification model are discussed. The contribution of this paper is a demonstration of how to assess the return on investment of model accuracy, in the context of a software quality classification model. An industrial case study of a very large telecommunications system illustrates the method. The dependent variable of the model was the probability that a module will have faults discovered by customers. The independent variables were software product and process metrics. The model is compared to random selection of modules for reliability enhancement. Calculation of return on investment can guide selection of the generalized classification rule's parameter so that the model is well-suited to the project.