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Lemaza : An Arabic why-question answering system*

  • AQIL M. AZMI (a1) and NOUF A. ALSHENAIFI (a1)

Question answering systems retrieve information from documents in response to queries. Most of the questions are who- and what-type questions that deal with named entities. A less common and more challenging question to deal with is the why -question. In this paper, we introduce Lemaza (Arabic for why), a system for automatically answering why -questions for Arabic texts. The system is composed of four main components that make use of the Rhetorical Structure Theory. To evaluate Lemaza, we prepared a set of why -question–answer pairs whose answer can be found in a corpus that we compiled out of Open Source Arabic Corpora. Lemaza performed best when the stop-words were not removed. The performance measure was 72.7%, 79.2% and 78.7% for recall, precision and c@1, respectively.

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We would like to thank W. Al-Sanie for sharing his RST implementation; and the language specialist for helping us with why-question–answer pairs. The first author would like to thank Miss Maryam for her assistance in proof-reading the manuscript. Special thanks to all three anonymous reviewers for their constructive comments, which helped in further improvement of the manuscript. This work was supported by a special fund in the Research Center of College of Computer & Information Sciences (CCIS) at King Saud University for which the authors are thankful.

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Natural Language Engineering
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