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Morphological disambiguation of Hebrew: a case study in classifier combination

Published online by Cambridge University Press:  26 July 2012

GENNADI LEMBERSKY
Affiliation:
Department of Computer Science, University of Haifa, Haifa, Israel e-mails: glembers@campus.haifa.ac.il, danny@shach.am, shuly@cs.haifa.ac.il
DANNY SHACHAM
Affiliation:
Department of Computer Science, University of Haifa, Haifa, Israel e-mails: glembers@campus.haifa.ac.il, danny@shach.am, shuly@cs.haifa.ac.il
SHULY WINTNER
Affiliation:
Department of Computer Science, University of Haifa, Haifa, Israel e-mails: glembers@campus.haifa.ac.il, danny@shach.am, shuly@cs.haifa.ac.il

Abstract

Morphological analysis and disambiguation are crucial stages in a variety of natural language processing applications, especially when languages with complex morphology are concerned. We present a system which disambiguates the output of a morphological analyzer for Hebrew. It consists of several simple classifiers and a module that combines them under the constraints imposed by the analyzer. We explore several approaches to classifier combination, as well as a back-off mechanism that relies on a large unannotated corpus. Our best result, around 83 percent accuracy, compares favorably with the state of the art on this task.

Type
Articles
Copyright
Copyright © Cambridge University Press 2012 

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