The relationship between test coverage and reliability

Models the relationship between testing effort, coverage and reliability, and presents a logarithmic model that relates testing effort to test coverage: statement (or block) coverage, branch (or decision) coverage, computation use (c-use) coverage, or predicate use (p-use) coverage. The model is based on the hypothesis that the enumerables (like branches or blocks) for any coverage measure have different detectability, just like the individual defects. This model allows us to relate a test coverage measure directly to the defect coverage. Data sets for programs with real defects are used to validate the model. The results are consistent with the known inclusion relationships among block, branch and p-use coverage measures. We show how the defect density controls the time-to-next-failure. The model can eliminate variables like the test application strategy from consideration. It is suitable for high-reliability applications where automatic (or manual) test generation is used to cover enemerables which have not yet been tested