{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,10]],"date-time":"2026-01-10T03:30:32Z","timestamp":1768015832301,"version":"3.49.0"},"reference-count":54,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2020,7,9]],"date-time":"2020-07-09T00:00:00Z","timestamp":1594252800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005710","name":"Universiti Teknologi Petronas","doi-asserted-by":"publisher","award":["YUTP-FRG\/015LC0240"],"award-info":[{"award-number":["YUTP-FRG\/015LC0240"]}],"id":[{"id":"10.13039\/501100005710","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Feature selection (FS) is a feasible solution for mitigating high dimensionality problem, and many FS methods have been proposed in the context of software defect prediction (SDP). Moreover, many empirical studies on the impact and effectiveness of FS methods on SDP models often lead to contradictory experimental results and inconsistent findings. These contradictions can be attributed to relative study limitations such as small datasets, limited FS search methods, and unsuitable prediction models in the respective scope of studies. It is hence critical to conduct an extensive empirical study to address these contradictions to guide researchers and buttress the scientific tenacity of experimental conclusions. In this study, we investigated the impact of 46 FS methods using Na\u00efve Bayes and Decision Tree classifiers over 25 software defect datasets from 4 software repositories (NASA, PROMISE, ReLink, and AEEEM). The ensuing prediction models were evaluated based on accuracy and AUC values. Scott\u2013KnottESD and the novel Double Scott\u2013KnottESD rank statistical methods were used for statistical ranking of the studied FS methods. The experimental results showed that there is no one best FS method as their respective performances depends on the choice of classifiers, performance evaluation metrics, and dataset. However, we recommend the use of statistical-based, probability-based, and classifier-based filter feature ranking (FFR) methods, respectively, in SDP. For filter subset selection (FSS) methods, correlation-based feature selection (CFS) with metaheuristic search methods is recommended. For wrapper feature selection (WFS) methods, the IWSS-based WFS method is recommended as it outperforms the conventional SFS and LHS-based WFS methods.<\/jats:p>","DOI":"10.3390\/sym12071147","type":"journal-article","created":{"date-parts":[[2020,7,10]],"date-time":"2020-07-10T09:45:31Z","timestamp":1594374331000},"page":"1147","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":60,"title":["Impact of Feature Selection Methods on the Predictive Performance of Software Defect Prediction Models: An Extensive Empirical Study"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7411-3639","authenticated-orcid":false,"given":"Abdullateef O.","family":"Balogun","sequence":"first","affiliation":[{"name":"Department of Computer and Information Science, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak 32610, Malaysia"},{"name":"Department of Computer Science, University of Ilorin, Ilorin, Ilorin 1515, Nigeria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1736-4834","authenticated-orcid":false,"given":"Shuib","family":"Basri","sequence":"additional","affiliation":[{"name":"Department of Computer and Information Science, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak 32610, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9300-4363","authenticated-orcid":false,"given":"Saipunidzam","family":"Mahamad","sequence":"additional","affiliation":[{"name":"Department of Computer and Information Science, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak 32610, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0038-3702","authenticated-orcid":false,"given":"Said J.","family":"Abdulkadir","sequence":"additional","affiliation":[{"name":"Department of Computer and Information Science, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak 32610, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3890-9792","authenticated-orcid":false,"given":"Malek A.","family":"Almomani","sequence":"additional","affiliation":[{"name":"Department of Software Engineering, The World Islamic Sciences and Education University, Amman 11947, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Victor E.","family":"Adeyemo","sequence":"additional","affiliation":[{"name":"School of Built Environment, Engineering and Computing, Leeds Beckett University, Headingley Campus, Leeds LS6 3QS, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7208-693X","authenticated-orcid":false,"given":"Qasem","family":"Al-Tashi","sequence":"additional","affiliation":[{"name":"Department of Computer and Information Science, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak 32610, Malaysia"},{"name":"Faculty of Administrative and Computer Sciences, University of Albaydha, Albaydha CV46+6X, Yemen"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2389-7039","authenticated-orcid":false,"given":"Hammed A.","family":"Mojeed","sequence":"additional","affiliation":[{"name":"Department of Computer Science, University of Ilorin, Ilorin, Ilorin 1515, Nigeria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abdullahi A.","family":"Imam","sequence":"additional","affiliation":[{"name":"Department of Computer and Information Science, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak 32610, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amos O.","family":"Bajeh","sequence":"additional","affiliation":[{"name":"Department of Computer Science, University of Ilorin, Ilorin, Ilorin 1515, Nigeria"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"50","DOI":"10.46792\/fuoyejet.v3i2.200","article-title":"Software Defect Prediction Using Ensemble Learning: An ANP Based Evaluation Method","volume":"3","author":"Balogun","year":"2018","journal-title":"FUOYE J. 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