TY - JOUR
T1 - Too trivial to test? An inverse view on defect prediction to identify methods with low fault risk
AU - Niedermayr, Rainer
AU - Röhm, Tobias
AU - Wagner, Stefan
N1 - Publisher Copyright:
© 2019 Niedermayr et al.
PY - 2019
Y1 - 2019
N2 - Background: Test resources are usually limited and therefore it is often not possible to completely test an application before a release. To cope with the problem of scarce resources, development teams can apply defect prediction to identify fault-prone code regions. However, defect prediction tends to low precision in cross-project prediction scenarios. Aims: We take an inverse view on defect prediction and aim to identify methods that can be deferred when testing because they contain hardly any faults due to their code being "trivial". We expect that characteristics of such methods might be project-independent, so that our approach could improve cross-project predictions. Method: We compute code metrics and apply association rule mining to create rules for identifying methods with low fault risk (LFR). We conduct an empirical study to assess our approach with six Java open-source projects containing precise fault data at the method level. Results: Our results show that inverse defect prediction can identify approx. 32-44% of the methods of a project to have a LFR; on average, they are about six times less likely to contain a fault than other methods. In cross-project predictions with larger, more diversified training sets, identified methods are even 11 times less likely to contain a fault. Conclusions: Inverse defect prediction supports the efficient allocation of test resources by identifying methods that can be treated with less priority in testing activities and is well applicable in cross-project prediction scenarios.
AB - Background: Test resources are usually limited and therefore it is often not possible to completely test an application before a release. To cope with the problem of scarce resources, development teams can apply defect prediction to identify fault-prone code regions. However, defect prediction tends to low precision in cross-project prediction scenarios. Aims: We take an inverse view on defect prediction and aim to identify methods that can be deferred when testing because they contain hardly any faults due to their code being "trivial". We expect that characteristics of such methods might be project-independent, so that our approach could improve cross-project predictions. Method: We compute code metrics and apply association rule mining to create rules for identifying methods with low fault risk (LFR). We conduct an empirical study to assess our approach with six Java open-source projects containing precise fault data at the method level. Results: Our results show that inverse defect prediction can identify approx. 32-44% of the methods of a project to have a LFR; on average, they are about six times less likely to contain a fault than other methods. In cross-project predictions with larger, more diversified training sets, identified methods are even 11 times less likely to contain a fault. Conclusions: Inverse defect prediction supports the efficient allocation of test resources by identifying methods that can be treated with less priority in testing activities and is well applicable in cross-project prediction scenarios.
KW - Fault risk
KW - Inverse defect prediction
KW - Low-fault-risk methods
KW - Testing
UR - http://www.scopus.com/inward/record.url?scp=85074164358&partnerID=8YFLogxK
U2 - 10.7717/peerj-cs.187
DO - 10.7717/peerj-cs.187
M3 - Article
AN - SCOPUS:85074164358
SN - 2376-5992
VL - 2019
JO - PeerJ Computer Science
JF - PeerJ Computer Science
IS - 4
M1 - e187
ER -