Fitting an Exponential Software Reliability Model to Field Failure Data.

摘要

The quantitative prediction and measurement of software reliability is of vital importance in the development of high quality cost effective software. Many software reliability models have been postulated in the literature, however few have been applied to field data. A model based upon the assumption that the failure rate of the software is proportional to the number of residual software errors leads to a constant failure rate and an exponential reliability function. The model contains two constants: the proportionality constant K and the initial (total) number of errors E sub T. This report utilizes a set of software development and field data taken as a vehicle to study the ease of calculation and the correspondence of the three methods of parameter estimation. The sensitivity of the reliability predictions to parameter changes are studied and compared with field results. The results show if data is carefully collected, software reliability models are practical and yield useful results. These can serve as one measure to help in choosing among competitive designs and as a guage of when to terminate the integration test phase.