Evaluating software degradation through entropy

Software systems are affected by degradation as an. effect of continuous ch ange. Since late interventions are too much onerous software degradation sh ould be detected early in the software lifetime. Software degradation is cu rrently detected by using many different complexity metrics, but their use to monitor maintenance activities is costly. These metrics are difficult to interpret, because each emphasizes a particular aspect of degradation and the aspects shown by different metrics are not orthogonal. The purpose of o ur research is to measure the entropy of a software system to assess its de gradation. In this paper, we partially validate the entropy class of metric s by a case study, replicated on successive releases of a set of software s ystems. The validity is shown through direct measures of software quality s uch as the number of detected defects, the maintenance effort and the numbe r of slipped defects.