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A New State-of-The-Art Czech Named Entity Recognizer

  • Jana Straková
  • Milan Straka
  • Jan Hajič
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8082)

Abstract

We present a new named entity recognizer for the Czech language. It reaches 82.82 F-measure on the Czech Named Entity Corpus 1.0 and significantly outperforms previously published Czech named entity recognizers. On the English CoNLL-2003 shared task, we achieved 89.16 F-measure, reaching comparable results to the English state of the art. The recognizer is based on Maximum Entropy Markov Model and a Viterbi algorithm decodes an optimal sequence labeling using probabilities estimated by a maximum entropy classifier. The classification features utilize morphological analysis, two-stage prediction, word clustering and gazetteers.

Keywords

named entities named entity recognition Czech 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Jana Straková
    • 1
  • Milan Straka
    • 1
  • Jan Hajič
    • 1
  1. 1.Faculty of Mathematics and Physics Institute of Formal and Applied LinguisticsCharles University in PraguePragueCzech Republic

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