{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,30]],"date-time":"2025-10-30T07:10:42Z","timestamp":1761808242860,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2019,2,19]],"date-time":"2019-02-19T00:00:00Z","timestamp":1550534400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/129600\/2017","SFRH\/BD\/93012\/2013","POCI-01-0145-FEDER-028857"],"award-info":[{"award-number":["SFRH\/BD\/129600\/2017","SFRH\/BD\/93012\/2013","POCI-01-0145-FEDER-028857"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>Several phenomena are represented by directional\u2014angular or periodic\u2014data; from time references on the calendar to geographical coordinates. These values are usually represented as real values restricted to a given range (e.g.,     [ 0 , 2 \u03c0 )    ), hiding the real nature of this information. In order to handle these variables properly in supervised classification tasks, alternatives to the naive Bayes classifier and logistic regression were proposed in the past. In this work, we propose directional-aware support vector machines. We address several realizations of the proposed models, studying their kernelized counterparts and their expressiveness. Finally, we validate the performance of the proposed Support Vector Machines (SVMs) against the directional naive Bayes and directional logistic regression with real data, obtaining competitive results.<\/jats:p>","DOI":"10.3390\/app9040725","type":"journal-article","created":{"date-parts":[[2019,2,20]],"date-time":"2019-02-20T03:05:52Z","timestamp":1550631952000},"page":"725","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Directional Support Vector Machines"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5246-0402","authenticated-orcid":false,"given":"Diogo","family":"Pernes","sequence":"first","affiliation":[{"name":"INESC TEC and University of Porto, 4200 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6838-9484","authenticated-orcid":false,"given":"Kelwin","family":"Fernandes","sequence":"additional","affiliation":[{"name":"INESC TEC and University of Porto, 4200 Porto, Portugal"},{"name":"NILG.AI, Porto, 4200 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3760-2473","authenticated-orcid":false,"given":"Jaime S.","family":"Cardoso","sequence":"additional","affiliation":[{"name":"INESC TEC and University of Porto, 4200 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1016\/S0167-9473(02)00181-0","article-title":"Fitting mixtures of von Mises distributions: A case study involving sudden infant death syndrome","volume":"41","author":"Mooney","year":"2003","journal-title":"Comput. 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