Search (4 results, page 1 of 1)

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Abstract

The use of Knowledge Organization Systems (KOSs) in aggregated metadata collections facilitates the implementation of search mechanisms operating on the same term or keyphrase space, thus preparing the ground for improved browsing, more accurate retrieval and better user profiling. Automatic thesaurus-based keyphrase extraction appears to be an inexpensive tool to obtain this information, but the studies on its effectiveness are scattered and do not consider the practical applicability of these techniques compared to the quality obtained by involving human experts. This paper presents an evaluation of keyphrase extraction using the KEA software and the AGROVOC vocabulary on a sample of a large collection of metadata in the field of agriculture from the AGRIS database. This effort includes a double evaluation, the classical automatic evaluation based on precision and recall measures, plus a blind evaluation aimed to contrast the quality of the keyphrases extracted against expert-provided samples and against the keyphrases originally recorded in the metadata. Results show not only that KEA outperforms humans in matching the original keyphrases, but also that the quality of the keyphrases extracted was similar to those provided by humans.

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Date

17. 1.2019 19:04:22

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Source

Wissensspeicher in digitalen Räumen: Nachhaltigkeit - Verfügbarkeit - semantische Interoperabilität. Proceedings der 11. Tagung der Deutschen Sektion der Internationalen Gesellschaft für Wissensorganisation, Konstanz, 20. bis 22. Februar 2008. Hrsg.: J. Sieglerschmidt u. H.P.Ohly

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Date

24. 8.2016 14:03:22