A test suite is executed to test a computer program for a plurality of variables. A variable value is generated for each variable of the plurality of variables at a predetermined location of the computer program. Whether a test included in the test suite is successful is determined. If the test is successful, the variable value is recorded as part of a success value set. If the test is not successful, the variable value is recorded as part of a failure value set. A confidence metric is calculated for the variable value. A relevance metric for each variable of the plurality of variables is measured, based on a Jaccard distance between the success value set and the failure value set. The failure value set, the success value set, the confidence metric for the variable value, and the relevance metric for each variable of the plurality of variables are presented.