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A naïve Bayes approach to classifying topics in suicide notes

Spasic, Irena ORCID:, Burnap, Peter ORCID:, Greenwood, Mark and Arribas-Ayllon, Michael ORCID: 2012. A naïve Bayes approach to classifying topics in suicide notes. Biomedical Informatics Insights 5 (Supp 1) , pp. 87-97. 10.4137/BII.S8945

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The authors present a system developed for the 2011 i2b2 Challenge on Sentiment Classification, whose aim was to automatically classify sentences in suicide notes using a scheme of 15 topics, mostly emotions. The system combines machine learning with a rule-based methodology. The features used to represent a problem were based on lexico–semantic properties of individual words in addition to regular expressions used to represent patterns of word usage across different topics. A naïve Bayes classifier was trained using the features extracted from the training data consisting of 600 manually annotated suicide notes. Classification was then performed using the naïve Bayes classifier as well as a set of pattern–matching rules. The classification performance was evaluated against a manually prepared gold standard consisting of 300 suicide notes, in which 1,091 out of a total of 2,037 sentences were associated with a total of 1,272 annotations. The competing systems were ranked using the micro-averaged F-measure as the primary evaluation metric. Our system achieved the F-measure of 53% (with 55% precision and 52% recall), which was significantly better than the average performance of 48.75% achieved by the 26 participating teams.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Social Sciences (Includes Criminology and Education)
Computer Science & Informatics
Subjects: H Social Sciences > H Social Sciences (General)
Q Science > QA Mathematics > QA75 Electronic computers. Computer science
Uncontrolled Keywords: natural language processing; sentiment analysis; topic classification; naïve Bayes classifier
Publisher: Libertas Academica Ltd
ISSN: 1178-2226
Last Modified: 18 Oct 2022 14:24

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