{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T13:24:12Z","timestamp":1780320252368,"version":"3.54.1"},"reference-count":57,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,5,27]],"date-time":"2023-05-27T00:00:00Z","timestamp":1685145600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Johannesburg","award":["KAO2019"],"award-info":[{"award-number":["KAO2019"]}]},{"name":"University Of Johannesburg Library, APC Fund","award":["KAO2019"],"award-info":[{"award-number":["KAO2019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Machine learning (ML) in wireless mobile communication is becoming more and more customary, with application trends leaning toward performance improvement and network automation. The radio access network (RAN), critical for service access, frequently generates performance data that mobile network operators (MNOs) and researchers leverage for planning, self-optimization, and intelligent network operations. However, missing values in the RAN performance data, as in any valuable data, impact analysis. Poor handling of such missing data in the RAN can distort the relationships between different metrics, leading to inaccurate and unreliable conclusions and predictions. Therefore, there is a need for imputation methods that preserve the overall structure of the RAN data to an optimal level. In this study, we present an imputation approach for handling RAN performance missing data based on machine learning algorithms. The method customizes the feature-extraction mechanism by using dynamic correlation analysis. We apply the method to actual RAN performance indicator data to evaluate its performance. We finally compare and evaluate the proposed approach with statistical imputation techniques such as the mean, median, and mode. The results show that machine learning-based imputation, as approached in this experimental study, preserves some relationships between KPIs compared to non-ML techniques. Random Forest regressor gave the best performance in imputing the data.<\/jats:p>","DOI":"10.3390\/sym15061161","type":"journal-article","created":{"date-parts":[[2023,5,27]],"date-time":"2023-05-27T16:10:53Z","timestamp":1685203853000},"page":"1161","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Machine Learning-Based Imputation Approach with Dynamic Feature Extraction for Wireless RAN Performance Data Preprocessing"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0938-2557","authenticated-orcid":false,"given":"Jean Nestor M.","family":"Dahj","sequence":"first","affiliation":[{"name":"Department of Electrical & Electronics Engineering Faculty of Engineering and the Built Environment, University of Johannesburg, Johannesburg 0524, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6589-4904","authenticated-orcid":false,"given":"Kingsley A.","family":"Ogudo","sequence":"additional","affiliation":[{"name":"Department of Electrical & Electronics Engineering Faculty of Engineering and the Built Environment, University of Johannesburg, Johannesburg 0524, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1109\/MIC.2017.3481355","article-title":"Network Slicing for 5G: Challenges and Opportunities","volume":"21","author":"Li","year":"2017","journal-title":"IEEE Internet Comput."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Anoh, K., See, C., Dama, Y., Abd-Alhameed, R., and Keates, S. 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