A Case Study to Investigate Sensitivity of Reliability Estimates to Errors in Operational Profile

Mei-Hwa Chen, Aditya P. Mathur and Vernon J. Rego

Software Engineering Research Center
Department of Computer Sciences
Purdue University
W. Lafayette, In 47907

ABSTRACT

We report a case study to investigate the effect of errors in an operational profile on reliability estimates. A previously reported tool named \terse/ was used in this study to generate random flow graphs representing programs, model errors in operational profile, and compute reliability estimates. Four models for reliability estimation were considered: the Musa-Okumoto model, the Goel-Okumoto model, coverage enhanced Musa-Okumoto model, and coverage enhanced Goel-Okumoto model. It was found that the error in reliability estimates from these models grows nonlinearly with errors in operational profil e. Results from this case study lend credit to the argument that further research is necessary in development of more robust models for reliability estimation.