Software reliability modeling and cost estimation incorporating testing-effort and efficiency

Abstract

Many studies have been performed on the subject of software reliability but few have explicitly considered the impact of software testing on the reliability process. This paper presents two important issues on software reliability modeling and software reliability economics: testing effort and efficiency. First, we discuss on how to extend the logistic testing-effort function into a general form. The generalized logistic testing-effort function has the advantage of relating the work profile more directly to the natural flow of software development. Therefore, it can be used to describe the actual consumption of resources during the software development process and to obtain a conspicuous improvement in modeling testing-effort expenditures. Furthermore, we incorporate the generalized logistic testing-effort function into software reliability modeling and its fault-prediction capability is evaluated through four numerical experiments on real data. Then, we address the effects of automated techniques or tools on increasing the efficiency of software testing. New testing techniques usually increase test coverage. We propose a modified software reliability cost model to reflect these effects. From the simulation results, we obtain a powerful software economic policy which clearly indicates the benefits of applying new automated testing techniques and tools during the software development process.