{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:40:10Z","timestamp":1760197210106,"version":"build-2065373602"},"reference-count":51,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,4,26]],"date-time":"2018-04-26T00:00:00Z","timestamp":1524700800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Informatics"],"abstract":"<jats:p>One of the major problems that social networks face is the continuous production of successful, user-targeted information in the form of recommendations, which are produced exploiting technology from the field of recommender systems. Recommender systems are based on information about users\u2019 past behavior to formulate recommendations about their future actions. However, as time goes by, social network users may change preferences and likings: they may like different types of clothes, listen to different singers or even different genres of music and so on. This phenomenon has been termed as concept drift. In this paper: (1) we establish that when a social network user abstains from rating submission for a long time, it is a strong indication that concept drift has occurred and (2) we present a technique that exploits the abstention interval concept, to drop from the database ratings that do not reflect the current social network user\u2019s interests, thus improving prediction quality.<\/jats:p>","DOI":"10.3390\/informatics5020021","type":"journal-article","created":{"date-parts":[[2018,4,27]],"date-time":"2018-04-27T06:52:23Z","timestamp":1524811943000},"page":"21","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Exploiting Rating Abstention Intervals for Addressing Concept Drift in Social Network Recommender Systems"],"prefix":"10.3390","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7487-374X","authenticated-orcid":false,"given":"Dionisis","family":"Margaris","sequence":"first","affiliation":[{"name":"Department of Informatics and Telecommunications, University of Athens, 15784 Athens, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9940-1821","authenticated-orcid":false,"given":"Costas","family":"Vassilakis","sequence":"additional","affiliation":[{"name":"Department of Informatics and Telecommunications, University of the Peloponnese, 22100 Tripolis, Greece"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,26]]},"reference":[{"key":"ref_1","unstructured":"(2018, January 05). 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