Testing Effort Dependent Delayed S-shaped Software Reliability Growth Model with Imperfect Debugging

In software development process, testing is one of the most important aspects and hence, software reliably is very important factor of software systems. In the last four decades many software reliability growth model based on non-homogeneous Poisson process (NHPP) have been developed which incorporates testing effort function. However, the previous models are quite helpful for software engineers/ developers and commonly applicable in the industries and research institution. Still more testing-effort functions are required to incorporate into software reliability growth model. In this paper, we develop delayed S-shaped software reliability growth model with imperfect debugging which incorporates new modified Weibull testing–effort function (NMWTEF). We estimate the testing effort model parameters by least square and S-shaped software reliability growth parameters by maximum likelihood estimation techniques. We also present confidence interval of the software reliability growth parameters. Various software reliability measures are investigated through three numerical experiments. The numerical results are compared with other existing models in the literature. It is shown that the proposed Delayed S-shaped Software Reliability Growth Model with imperfect debugging with NMWTEF has a fairly better errors prediction capability. KeywordsSoftware Testing, Software Reliability Growth, Testing Effort Functions, Least Square estimation, Maximum Likelihood estimation