Named Entity Recognition for Highly Inflectional Languages: Effects of Various Lemmatization and Stemming Approaches

  • Michal Konkol
  • Miloslav Konopík
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8655)


In this paper, we study the effects of various lemmatization and stemming approaches on the named entity recognition (NER) task for Czech, a highly inflectional language. Lemmatizers are seen as a necessary component for Czech NER systems and they were used in all published papers about Czech NER so far. Thus, it has an utmost importance to explore their benefits, limits and differences between simple and complex methods. Our experiments are evaluated on the standard Czech Named Entity Corpus 1.1 as well as the newly created 2.0 version.


Named Entity Recognition Lemmatization Stemming 


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© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Michal Konkol
    • 1
  • Miloslav Konopík
    • 1
  1. 1.Department of Computer Science and Engineering, Faculty of Applied SciencesUniversity of West BohemiaPlzeňCzech Republic

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