ON THE EXPECTED NUMBER OF FAILURES DETECTED BY SUBDOMAIN TESTING AND RANDOM TESTING

In this paper, we investigate the efficacy of subdomain testing and ra ndom testing using the expected number of failures detected (the E-mea sure) as a measure of effectiveness. Simple as it is, the E-measure do es provide a great deal of useful information about the fault-detectin g capability of testing strategies. With the E-measure, we obtain new characterizations of subdomain testing, including several new conditio ns that determine whether subdomain testing is more or less effective than random testing. Previously, the efficacy ct subdomain testing str ategies has been analyzed using the probability of detecting at least one failure (the P-measure) for the special case of disjoint subdomain s only. On the contrary, our analysis makes use of the E-measure and c onsiders also the general case in which subdomains may or may not over lap. Furthermore, we discover important relations between the two diff erent measures. From these relations, we also derive corresponding cha racterizations of subdomain testing in terms of the P-measure.