Reliability Analysis of a Two-Stage Goel-Okumoto and Yamada S-shaped Model

Abstract

Software systems are becoming essential parts in many products. These are most commonly home devices and other industrial and commercial products. Nowadays, with this increasing dependence on software systems, the size and the complexity of the software products has increased dramatically. The interest on software systems has led to the development of techniques on software reliability assessment such as the Non-Homogeneous Poisson Process Models, Goel-Okumoto and Yamada S-shaped models. This paper is an analysis on the reliability of the software program of a large telecommunication company. An estimation of the Goel-Okumoto model parameters were given with the Matlab program, and the parameters of the Yamada’s S-shaped model were estimated with the SMERFS software reliability tool. Additionally, we assume that new code is inserted into the software and we estimate the parameters of both models. A detailed examination of the results led us conclude that the Yamada’s S-shaped model is the most appropriate model.KeywordsNHPP modelsSMERFSsoftware reliability measurementGoel- Okumoto modelYamada S-shaped model2-stage models