A Review of Pre-Release Metrics used for Predicting Post- Release Defects

Software maintenance has consumed more than 50% of development effort and about 90% of software lifecycle. Finding and correcting defects after software delivery have often presented high costs when compared to correct it on previous project phases. The defects that are found after the release of a product are known as post release software defects. To detect these defects before the release of the product mainly two metrics are used that are the Mean Time between Failures (MTBF) and the Average usage Time (AVT).These metrics are frequently used to gauge the reliability of the application. However, MTBF and AVT cannot capture the whole pattern of failure occurrences in the field testing of an application. In this paper, three metrics that capture three additional patterns of failure occurrences: the average length of usage time before the occurrence of the first failure, the spread of failures to the majority of users, and the daily rates of failures are described.