Exploring the relationships between design measures and software quality in object-oriented systems

One goal of this paper is to empirically explore the relationships between existing object-oriented (OO) coupling, cohesion, and inheritance measures and the probability of fault detection in system classes during testing. In other words, we wish to better understand the relationship between existin g design measurement in OO systems and the quality of the software develope d. The second goal is to propose an investigation and analysis strategy to make these kind of studies more repeatable and comparable, a problem which is pervasive in the literature on quality measurement. Results show that ma ny of the measures capture similar dimensions in the data set, thus reflect ing the fact that many of them are based on similar principles and hypothes es. However, it is shown that by using a subset of measures, accurate model s can be built to predict which classes most of the faults are likely to li e in. When predicting fault-prone classes, the best model shows a percentag e of correct classifications higher than 80% and finds more than 90% of fau lty classes. Besides the size of classes, the frequency of method invocatio ns and the depth of inheritance hierarchies seem to be the main driving fac tors of fault-proneness. (C) 2000 Elsevier Science Inc. All rights reserved .