{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T10:05:04Z","timestamp":1777889104348,"version":"3.51.4"},"reference-count":83,"publisher":"Association for Computing Machinery (ACM)","issue":"3","license":[{"start":{"date-parts":[[2021,4,27]],"date-time":"2021-04-27T00:00:00Z","timestamp":1619481600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.acm.org\/publications\/policies\/copyright_policy#Background"}],"content-domain":{"domain":["dl.acm.org"],"crossmark-restriction":true},"short-container-title":["J. Data and Information Quality"],"published-print":{"date-parts":[[2021,9,30]]},"abstract":"<jats:p>E-learning recommender systems are gaining significance nowadays due to its ability to enhance the learning experience by providing tailor-made services based on learner preferences. A Personalized Learning Environment (PLE) that automatically adapts to learner characteristics such as learning styles and knowledge level can recommend appropriate learning resources that would favor the learning process and improve learning outcomes. The pure cold-start problem is a relevant issue in PLEs, which arises due to the lack of prior information about the new learner in the PLE to create appropriate recommendations. This article introduces a semantic framework based on ontology to address the pure cold-start problem in content recommenders. The ontology encapsulates the domain knowledge about the learners as well as Learning Objects (LOs). The semantic model that we built has been experimented with different combinations of the key learner parameters such as learning style, knowledge level, and background knowledge. The proposed framework utilizes these parameters to build natural learner groups from the learner ontology using SPARQL queries. The ontology holds 480 learners\u2019 data, 468 annotated learning objects with 5,600 learner ratings. A multivariate k-means clustering algorithm, an unsupervised machine learning technique for grouping similar data, is used to evaluate the learner similarity computation accuracy. The learner satisfaction achieved with the proposed model is measured based on the ratings given by the 40 participants of the experiments. From the evaluation perspective, it is evident that 79% of the learners are satisfied with the recommendations generated by the proposed model in pure cold-start condition.<\/jats:p>","DOI":"10.1145\/3429251","type":"journal-article","created":{"date-parts":[[2021,4,27]],"date-time":"2021-04-27T14:14:25Z","timestamp":1619532865000},"page":"1-27","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":33,"title":["Ontology-based E-learning Content Recommender System for Addressing the Pure Cold-start Problem"],"prefix":"10.1145","volume":"13","author":[{"given":"Jeevamol","family":"Joy","sequence":"first","affiliation":[{"name":"Cochin University of Science and Technology, India"}]},{"given":"Nisha S.","family":"Raj","sequence":"additional","affiliation":[{"name":"Cochin University of Science and Technology, India"}]},{"given":"Renumol","family":"V. G.","sequence":"additional","affiliation":[{"name":"Cochin University of Science and Technology, India"}]}],"member":"320","published-online":{"date-parts":[[2021,4,27]]},"reference":[{"key":"e_1_2_1_1_1","doi-asserted-by":"publisher","DOI":"10.1046\/j.1360-3736.2003.00184.x"},{"key":"e_1_2_1_2_1","doi-asserted-by":"publisher","DOI":"10.1145\/986213.986216"},{"key":"e_1_2_1_3_1","doi-asserted-by":"publisher","DOI":"10.1145\/3148240"},{"key":"e_1_2_1_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.knosys.2013.03.012"},{"key":"e_1_2_1_5_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.is.2014.10.001"},{"key":"e_1_2_1_6_1","doi-asserted-by":"publisher","DOI":"10.7763\/LNSE.2013.V1.66"},{"key":"e_1_2_1_7_1","doi-asserted-by":"crossref","unstructured":"Y. Koren and R. Bell. 2015. Advances in collaborative filtering. In Recommender Systems Handbook. Springer Boston MA 77\u2013118.  Y. Koren and R. Bell. 2015. Advances in collaborative filtering. In Recommender Systems Handbook. Springer Boston MA 77\u2013118.","DOI":"10.1007\/978-1-4899-7637-6_3"},{"key":"e_1_2_1_8_1","doi-asserted-by":"publisher","DOI":"10.1155\/2009\/421425"},{"key":"e_1_2_1_9_1","doi-asserted-by":"publisher","DOI":"10.5555\/1768197.1768209"},{"key":"e_1_2_1_10_1","doi-asserted-by":"publisher","DOI":"10.1145\/564376.564421"},{"key":"e_1_2_1_11_1","doi-asserted-by":"publisher","DOI":"10.1145\/1352793.1352837"},{"key":"e_1_2_1_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ins.2016.10.009"},{"key":"e_1_2_1_13_1","volume-title":"Proceedings of the International Joint Conference on Neural Networks (IJCNN\u201917)","author":"Majumdar A.","unstructured":"A. Majumdar and A. Jain . 2017. Cold-start, warm-start and everything in between: An autoencoder based approach to recommendation . In Proceedings of the International Joint Conference on Neural Networks (IJCNN\u201917) . IEEE, 3656\u20133663. A. Majumdar and A. Jain. 2017. Cold-start, warm-start and everything in between: An autoencoder based approach to recommendation. In Proceedings of the International Joint Conference on Neural Networks (IJCNN\u201917). IEEE, 3656\u20133663."},{"key":"e_1_2_1_14_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.compedu.2010.11.001"},{"key":"e_1_2_1_15_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.chb.2011.09.002"},{"key":"e_1_2_1_16_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.chb.2009.12.010"},{"key":"e_1_2_1_17_1","volume-title":"Proceedings of the IEEE 10th International Conference on Technology for Education (T4E\u201919)","author":"Raj N. S.","unstructured":"N. S. Raj and V. G. Renumol . 2019. A rule-based approach for adaptive content recommendation in a personalized learning environment: An experimental analysis . In Proceedings of the IEEE 10th International Conference on Technology for Education (T4E\u201919) . 138\u2013141. N. S. Raj and V. G. Renumol. 2019. A rule-based approach for adaptive content recommendation in a personalized learning environment: An experimental analysis. In Proceedings of the IEEE 10th International Conference on Technology for Education (T4E\u201919). 138\u2013141."},{"key":"e_1_2_1_18_1","doi-asserted-by":"publisher","DOI":"10.3758\/s13428-018-1166-9"},{"key":"e_1_2_1_19_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.compedu.2019.04.009"},{"key":"e_1_2_1_20_1","doi-asserted-by":"publisher","DOI":"10.5555\/3220755.3220875"},{"key":"e_1_2_1_21_1","doi-asserted-by":"publisher","DOI":"10.1145\/3368691.3368700"},{"key":"e_1_2_1_22_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.knosys.2013.03.012"},{"key":"e_1_2_1_23_1","doi-asserted-by":"publisher","DOI":"10.1145\/2792838.2800196"},{"key":"e_1_2_1_24_1","volume-title":"Proceedings of the International Conference on User Modeling, Adaptation, and Personalization. Springer, Cham, 289\u2013301","author":"Wongchokprasitti C.","unstructured":"C. Wongchokprasitti , J. Peltonen , T. Ruotsalo , P. Bandyopadhyay , G. Jacucci , and P. Brusilovsky . 2015. User model in a box: Cross-system user model transfer for resolving cold start problems . In Proceedings of the International Conference on User Modeling, Adaptation, and Personalization. Springer, Cham, 289\u2013301 . C. Wongchokprasitti, J. Peltonen, T. Ruotsalo, P. Bandyopadhyay, G. Jacucci, and P. Brusilovsky. 2015. User model in a box: Cross-system user model transfer for resolving cold start problems. In Proceedings of the International Conference on User Modeling, Adaptation, and Personalization. Springer, Cham, 289\u2013301."},{"key":"e_1_2_1_25_1","doi-asserted-by":"publisher","DOI":"10.1145\/1150402.1150490"},{"key":"e_1_2_1_26_1","doi-asserted-by":"publisher","DOI":"10.1145\/564376.564421"},{"key":"e_1_2_1_27_1","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-13657-3_37"},{"key":"e_1_2_1_28_1","doi-asserted-by":"publisher","DOI":"10.1142\/9789812799470_0144"},{"key":"e_1_2_1_29_1","doi-asserted-by":"publisher","DOI":"10.1209\/0295-5075\/92\/28002"},{"key":"e_1_2_1_30_1","doi-asserted-by":"publisher","DOI":"10.1109\/ICDM.2010.129"},{"key":"e_1_2_1_31_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.knosys.2011.07.021"},{"key":"e_1_2_1_32_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ins.2007.07.024"},{"key":"e_1_2_1_33_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.knosys.2015.02.016"},{"key":"e_1_2_1_34_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.is.2018.09.001"},{"key":"e_1_2_1_35_1","doi-asserted-by":"publisher","DOI":"10.1109\/WAINA.2011.12"},{"key":"e_1_2_1_36_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10586-014-0355-2"},{"key":"e_1_2_1_37_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.is.2015.07.008"},{"key":"e_1_2_1_38_1","doi-asserted-by":"publisher","DOI":"10.1145\/2076623.2076662"},{"key":"e_1_2_1_39_1","volume-title":"Proceedings of the International Conference on Computer Communication and Informatics. IEEE, 1\u20135","author":"Sobhanam H.","unstructured":"H. Sobhanam and A. K. Mariappan . 2013. Addressing cold start problem in recommender systems using association rules and clustering technique . In Proceedings of the International Conference on Computer Communication and Informatics. IEEE, 1\u20135 H. Sobhanam and A. K. Mariappan. 2013. Addressing cold start problem in recommender systems using association rules and clustering technique. In Proceedings of the International Conference on Computer Communication and Informatics. IEEE, 1\u20135"},{"key":"e_1_2_1_40_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.future.2017.02.049"},{"key":"e_1_2_1_41_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.eswa.2016.02.013"},{"key":"e_1_2_1_42_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.aci.2017.07.003"},{"key":"e_1_2_1_43_1","doi-asserted-by":"publisher","DOI":"10.1145\/2968332"},{"key":"e_1_2_1_44_1","doi-asserted-by":"publisher","DOI":"10.1109\/TKDE.2005.99"},{"key":"e_1_2_1_45_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10844-014-0334-3"},{"key":"e_1_2_1_46_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.chb.2016.08.030"},{"key":"e_1_2_1_47_1","first-page":"12","article-title":"Ontology-based semantic approach for learning object recommendation","volume":"3","author":"Pukkhem N.","year":"2013","unstructured":"N. Pukkhem . 2013 . Ontology-based semantic approach for learning object recommendation . Int. J. Inf. Technol. 3 , 4 (2013), 12 . N. Pukkhem. 2013. Ontology-based semantic approach for learning object recommendation. Int. J. Inf. Technol. 3, 4 (2013), 12.","journal-title":"Int. J. Inf. Technol."},{"key":"e_1_2_1_48_1","volume-title":"Proceedings of the International Conference on Electrical and Information Technologies (ICEIT\u201917)","author":"Bouihi B.","unstructured":"B. Bouihi and M. Bahaj . 2017. An ontology-based architecture for context recommendation system in E-learning and mobile-learning applications . In Proceedings of the International Conference on Electrical and Information Technologies (ICEIT\u201917) . IEEE, 1\u20136. B. Bouihi and M. Bahaj. 2017. An ontology-based architecture for context recommendation system in E-learning and mobile-learning applications. In Proceedings of the International Conference on Electrical and Information Technologies (ICEIT\u201917). IEEE, 1\u20136."},{"key":"e_1_2_1_49_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.jksuci.2014.03.007"},{"key":"e_1_2_1_50_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10956-006-9019-1"},{"key":"e_1_2_1_51_1","doi-asserted-by":"publisher","DOI":"10.17706\/jsw.10.3.317-330"},{"key":"e_1_2_1_52_1","volume-title":"Proceedings of the IEEE\/ACS 14th International Conference on Computer Systems and Applications (AICCSA\u201917)","author":"Harrathi M.","unstructured":"M. Harrathi , N. Touzani , and R. Braham . 2017. A hybrid knowledge-based approach for recommending massive learning activities . In Proceedings of the IEEE\/ACS 14th International Conference on Computer Systems and Applications (AICCSA\u201917) . 49\u201354. M. Harrathi, N. Touzani, and R. Braham. 2017. A hybrid knowledge-based approach for recommending massive learning activities. In Proceedings of the IEEE\/ACS 14th International Conference on Computer Systems and Applications (AICCSA\u201917). 49\u201354."},{"key":"e_1_2_1_53_1","doi-asserted-by":"publisher","DOI":"10.1145\/3184558.3191533"},{"key":"e_1_2_1_54_1","first-page":"115","article-title":"Ontological approach in knowledge based recommender system to develop the quality of e-learning system","volume":"6","author":"Shishehchi S.","year":"2012","unstructured":"S. Shishehchi , S. Y. Banihashem , N. A. M. Zin , S. A. M. Noah , and K. Malaysia . 2012 . Ontological approach in knowledge based recommender system to develop the quality of e-learning system . Austral. J. Basic Appl. Sci. 6 , 2 (2012), 115 \u2013 123 . S. Shishehchi, S. Y. Banihashem, N. A. M. Zin, S. A. M. Noah, and K. Malaysia. 2012. Ontological approach in knowledge based recommender system to develop the quality of e-learning system. Austral. J. Basic Appl. Sci. 6, 2 (2012), 115\u2013123.","journal-title":"Austral. J. Basic Appl. Sci."},{"key":"e_1_2_1_55_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.compedu.2019.103642"},{"key":"e_1_2_1_56_1","doi-asserted-by":"publisher","DOI":"10.1109\/IUCE.2009.128"},{"key":"e_1_2_1_57_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.advengsoft.2008.10.006"},{"key":"e_1_2_1_58_1","doi-asserted-by":"publisher","DOI":"10.5555\/1717561.1717745"},{"key":"e_1_2_1_59_1","article-title":"An ontology approach to represent user profiles in e-learning","volume":"2","author":"Sheeba T.","year":"2013","unstructured":"T. Sheeba and S. H. Begum . 2013 . An ontology approach to represent user profiles in e-learning . Int. J. Eng. Res. Technol. 2 , 2 (2013). T. Sheeba and S. H. Begum. 2013. An ontology approach to represent user profiles in e-learning. Int. J. Eng. Res. Technol. 2, 2 (2013).","journal-title":"Int. J. Eng. Res. Technol."},{"key":"e_1_2_1_60_1","volume-title":"Proceedings of the International Conference on Computational Science and Its Applications. Springer, Cham, 199\u2013212","author":"Ciloglugil B.","unstructured":"B. Ciloglugil and M. M. Inceoglu . 2018. A learner ontology based on learning style models for adaptive e-learning . In Proceedings of the International Conference on Computational Science and Its Applications. Springer, Cham, 199\u2013212 . B. Ciloglugil and M. M. Inceoglu. 2018. A learner ontology based on learning style models for adaptive e-learning. In Proceedings of the International Conference on Computational Science and Its Applications. Springer, Cham, 199\u2013212."},{"key":"e_1_2_1_61_1","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-31137-6_42"},{"key":"e_1_2_1_62_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.chb.2015.02.014"},{"key":"e_1_2_1_63_1","volume-title":"Proceedings of the International Conference on Brain Inspired Cognitive Systems. Springer, Cham, 284\u2013297","author":"Sheeba T.","unstructured":"T. Sheeba and R. Krishnan . 2016. An ontological framework of semantic learner profile in an e-learning system . In Proceedings of the International Conference on Brain Inspired Cognitive Systems. Springer, Cham, 284\u2013297 . T. Sheeba and R. Krishnan. 2016. An ontological framework of semantic learner profile in an e-learning system. In Proceedings of the International Conference on Brain Inspired Cognitive Systems. Springer, Cham, 284\u2013297."},{"key":"e_1_2_1_64_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.dss.2007.05.004"},{"key":"e_1_2_1_65_1","article-title":"Personalized students\u2019 profile based on ontology and rule-based reasoning","volume":"3","author":"Nafea S.","year":"2016","unstructured":"S. Nafea , L. Maglaras , F. Siewe , R. Smith , and H. Janicke . 2016 . Personalized students\u2019 profile based on ontology and rule-based reasoning . ICST Trans. 3 , 12 (2016). S. Nafea, L. Maglaras, F. Siewe, R. Smith, and H. Janicke. 2016. Personalized students\u2019 profile based on ontology and rule-based reasoning. ICST Trans. 3, 12 (2016).","journal-title":"ICST Trans."},{"key":"e_1_2_1_66_1","doi-asserted-by":"publisher","DOI":"10.1007\/s11280-012-0187-z"},{"key":"e_1_2_1_67_1","first-page":"674","article-title":"Learning and teaching styles in engineering education","volume":"78","author":"Felder R. M.","year":"1988","unstructured":"R. M. Felder and L. K. Silverman . 1988 . Learning and teaching styles in engineering education . Eng. Educ. 78 , 7 (1988), 674 \u2013 681 . R. M. Felder and L. K. Silverman. 1988. Learning and teaching styles in engineering education. Eng. Educ. 78, 7 (1988), 674\u2013681.","journal-title":"Eng. Educ."},{"key":"e_1_2_1_68_1","article-title":"Use and abuse of reusable learning objects","volume":"14","author":"Polsani P.","year":"2003","unstructured":"P. Polsani . 2003 . Use and abuse of reusable learning objects . J. Dig. Inf. 14 , 10 (2012). Retrieved from https:\/\/journals.tdl.org\/jodi\/index.php\/jodi\/article\/viewArticle\/89\/88. P. Polsani. 2003. Use and abuse of reusable learning objects. J. Dig. Inf. 14, 10 (2012). Retrieved from https:\/\/journals.tdl.org\/jodi\/index.php\/jodi\/article\/viewArticle\/89\/88.","journal-title":"J. Dig. Inf."},{"key":"e_1_2_1_69_1","volume-title":"Proceedings of the International Conference on New Trends in Education (ICNTE\u201916)","author":"Ciloglugil B.","unstructured":"B. Ciloglugil and M. M. Inceoglu . 2016. Ontology usage in e-learning systems focusing on metadata modeling of learning objects . In Proceedings of the International Conference on New Trends in Education (ICNTE\u201916) . 80\u201396. B. Ciloglugil and M. M. Inceoglu. 2016. Ontology usage in e-learning systems focusing on metadata modeling of learning objects. In Proceedings of the International Conference on New Trends in Education (ICNTE\u201916). 80\u201396."},{"key":"e_1_2_1_70_1","first-page":"67","article-title":"Ontologies in e-learning: review of the literature","volume":"9","author":"Al-Yahya M.","year":"2015","unstructured":"M. Al-Yahya , R. George , and A. Alfaries . 2015 . Ontologies in e-learning: review of the literature . Int. J. Softw. Eng. Its Applic. 9 , 2 (2015), 67 \u2013 84 . M. Al-Yahya, R. George, and A. Alfaries. 2015. Ontologies in e-learning: review of the literature. Int. J. Softw. Eng. Its Applic. 9, 2 (2015), 67\u201384.","journal-title":"Int. J. Softw. Eng. Its Applic."},{"key":"e_1_2_1_71_1","volume-title":"Autom. Constr. 22","author":"Raju P.","year":"2012","unstructured":"P. Raju and V. Ahmed . 2012. Enabling technologies for developing next-generation learning object repository for construction . Autom. Constr. 22 , ( 2012 ), 247\u2013257. P. Raju and V. Ahmed. 2012. Enabling technologies for developing next-generation learning object repository for construction. Autom. Constr. 22, (2012), 247\u2013257."},{"key":"e_1_2_1_72_1","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-33263-0_38"},{"key":"e_1_2_1_73_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.procs.2013.12.011"},{"key":"e_1_2_1_74_1","volume-title":"Recent Advances in Information and Communication Technology","author":"Pukkhem N.","unstructured":"N. Pukkhem . 2014. LORecommendNet: An ontology-based representation of learning object recommendation . In Recent Advances in Information and Communication Technology . Springer , Cham , 293\u2013303. N. Pukkhem. 2014. LORecommendNet: An ontology-based representation of learning object recommendation. In Recent Advances in Information and Communication Technology. Springer, Cham, 293\u2013303."},{"key":"e_1_2_1_75_1","volume-title":"Proceedings of the 8th World Congress on Intelligent Control and Automation. IEEE, 2746\u20132750","author":"Han Q.","unstructured":"Q. Han , F. Gao , and H. Wang . 2010. Ontology-based learning object recommendation for cognitive considerations . In Proceedings of the 8th World Congress on Intelligent Control and Automation. IEEE, 2746\u20132750 . Q. Han, F. Gao, and H. Wang. 2010. Ontology-based learning object recommendation for cognitive considerations. In Proceedings of the 8th World Congress on Intelligent Control and Automation. IEEE, 2746\u20132750."},{"key":"e_1_2_1_76_1","doi-asserted-by":"publisher","DOI":"10.17706\/jsw.10.3.317-330"},{"key":"e_1_2_1_77_1","volume-title":"Proceedings of the International Conference on Information and Management Engineering. Springer","author":"Huang C.","unstructured":"C. Huang , L. Liu , Y. Tang , and L. Lu . 2011. Semantic web enabled personalized recommendation for learning paths and experiences . In Proceedings of the International Conference on Information and Management Engineering. Springer , Berlin, 258\u2013267. C. Huang, L. Liu, Y. Tang, and L. Lu. 2011. Semantic web enabled personalized recommendation for learning paths and experiences. In Proceedings of the International Conference on Information and Management Engineering. Springer, Berlin, 258\u2013267."},{"key":"e_1_2_1_78_1","volume-title":"Draft standard for learning object metadata","author":"Risk U.","year":"2002","unstructured":"U. Risk . 2002. Draft standard for learning object metadata . IEEE Standard ( 2002 ), 1484, 1. Retrieved from http:\/\/www.dia.uniroma3.it\/\u223csciarro\/e-learning\/LOM_1484_12_1_v1_Final_Draft.pdf. U. Risk. 2002. Draft standard for learning object metadata. IEEE Standard (2002), 1484, 1. Retrieved from http:\/\/www.dia.uniroma3.it\/\u223csciarro\/e-learning\/LOM_1484_12_1_v1_Final_Draft.pdf."},{"key":"e_1_2_1_79_1","unstructured":"E. Prud'hommeaux and A. Seaborne. 2006. SPARQL query language for RDF. w3c working draft. World Wide Web Consortium. http:\/\/www.w3.org\/TR\/rdf-sparql-query.  E. Prud'hommeaux and A. Seaborne. 2006. SPARQL query language for RDF. w3c working draft. World Wide Web Consortium. http:\/\/www.w3.org\/TR\/rdf-sparql-query."},{"key":"e_1_2_1_80_1","doi-asserted-by":"crossref","unstructured":"N. Manouselis H. Drachsler R. Vuorikari H. Hummel and R. Koper. 2011. Recommender systems in technology enhanced learning. In Recommender Systems Handbook. Springer Boston MA 387\u2013415.  N. Manouselis H. Drachsler R. Vuorikari H. Hummel and R. Koper. 2011. Recommender systems in technology enhanced learning. In Recommender Systems Handbook. Springer Boston MA 387\u2013415.","DOI":"10.1007\/978-0-387-85820-3_12"},{"key":"e_1_2_1_81_1","volume-title":"Introduction to Multivariate Analysis","author":"Chatfield C.","unstructured":"C. Chatfield . 2018. Introduction to Multivariate Analysis . Routledge . C. Chatfield. 2018. Introduction to Multivariate Analysis. Routledge."},{"key":"e_1_2_1_82_1","volume-title":"Advances in K-means Clustering","author":"Wu J.","unstructured":"J. Wu . 2012. Cluster analysis and K-means clustering: An introduction . In Advances in K-means Clustering . Springer , Berlin , 1\u201316. J. Wu. 2012. Cluster analysis and K-means clustering: An introduction. In Advances in K-means Clustering. Springer, Berlin, 1\u201316."},{"key":"e_1_2_1_83_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ins.2015.03.062"}],"container-title":["Journal of Data and Information Quality"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dl.acm.org\/doi\/10.1145\/3429251","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/dl.acm.org\/doi\/pdf\/10.1145\/3429251","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,6,17]],"date-time":"2025-06-17T22:02:33Z","timestamp":1750197753000},"score":1,"resource":{"primary":{"URL":"https:\/\/dl.acm.org\/doi\/10.1145\/3429251"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,4,27]]},"references-count":83,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2021,9,30]]}},"alternative-id":["10.1145\/3429251"],"URL":"https:\/\/doi.org\/10.1145\/3429251","relation":{},"ISSN":["1936-1955","1936-1963"],"issn-type":[{"value":"1936-1955","type":"print"},{"value":"1936-1963","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,4,27]]},"assertion":[{"value":"2020-02-01","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2020-10-01","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2021-04-27","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}