Unlexicalized Dependency Parser for Variable Word Order Languages Based on Local Contextual Pattern

  • Hoojung Chung
  • Hae-Chang Rim
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2945)

Abstract

We investigate the effect of unlexicalization in a dependency parser for variable word order languages and propose an unlexicalized parser which can utilize some contextual information in order to achieve performance comparable to that of lexicalized parsers. Unlexicalization of an early dependency parser makes performance decrease by 3.6%. However, when we modify the unlexicalized parser into the one which can consider additional contextual information, the parser performs better than some lexicalized dependency parsers, while it requires simpler smoothing processes, less time and space for parsing.

Keywords

Word Order Dependency Relation Distance Probability Dependency Parser Phrase Structure Grammar 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Collins, M.: Head-Driven Statistical Models for Natural Language Parsing. PhD thesis, University of Pennsylvania (1999)Google Scholar
  2. 2.
    Charniak, E.: A maximum-entropy-inspired parser. Technical Report CS-99-12, Department of Computer Science, Brown University (1999)Google Scholar
  3. 3.
    Charniak, E.: Immediate-head parsing for language models. In: Meeting of the Association for Computational Linguistics, pp. 116–123 (2001)Google Scholar
  4. 4.
    Gildea, D.: Corpus variation and parser performance. In: Proceedings of Conference on Empirical Methods in Natural Language Processing (2001)Google Scholar
  5. 5.
    Klein, D., Manning, C.D.: Accurate unlexicalized parsing. In: Proceedings of the 41st Meeting of the Association for Computational Linguistics, pp. 310–315 (2003)Google Scholar
  6. 6.
    Collins, M.J.: A new statistical parser based on bigram lexical dependencies. In: Proceedings of the 34th Annual Meeting of the ACL (1996)Google Scholar
  7. 7.
    Lee, K.J.: Probabilistic Parsing of Korean based on Language-Specific Properties. PhD thesis, Dept. of Computer Science. KAIST (1997)Google Scholar
  8. 8.
    Haruno, M., Shirai, S., Ooyama, Y.: Using decision trees to construct a practical parser. In: Proceedings of COLING-ACL 1998, pp. 505–512 (1998)Google Scholar
  9. 9.
    Kim, H., Seo, J.: A statistical Korean parser based on lexical dependencies. In: Spring Proceedings of Conference on Korea AI Society (1997)Google Scholar
  10. 10.
    Uchimoto, K., Sekine, S., Isahara, H.: Japanese dependency structure analysis based on maximum entropy models. In: Proceedings of 13th EACL, pp. 196–203 (1999)Google Scholar
  11. 11.
    Kanayama, H., Torisawa, K., Mitsuichi, Y., Tsujii, J.: Statistical dependency analysis with an HPSG-based Japanese grammar. In: Proceedings of 5th Natural Language Processing Pacific Rim Symposium, pp. 138–143 (1999)Google Scholar
  12. 12.
    Kanayama, H., Torisawa, K., Mitsuichi, Y., Tsujii, J.: A hybrid Japanese parser with an hand-crafted grammar and statistics. In: Proceedings of the COLING 2000, pp. 411–417 (2000)Google Scholar
  13. 13.
    Sekine, S., Uchimoto, K., Isahara, H.: Backward beam search algorithm for dependency analysis of japanese. In: Proceedings of the COLING 2000, pp. 745–760 (2000)Google Scholar
  14. 14.
    Choi, K.S.: KAIST Language Resources v.2001. Result of Core Software Project from Ministry of Science and Technology, Korea (2001), http://kibs.kaist.ac.kr
  15. 15.
    Sekine, S.: Japanese dependency analysis using a deterministic definite state transducer. In: Proceedings of the COLING 2000, pp. 761–767 (2000)Google Scholar
  16. 16.
    Charniak, E.: Tree-bank grammars. Technical Report CS-96-02, Department of Computer Science, Brown University (1996)Google Scholar
  17. 17.
    Seo, K.J., Nam, K.C., Choi, K.S.: A probabilistic model of the dependency parse for the variable-word-order languages by using ascending dependency. Computer Processing of Oriental Languages 12, 309–322 (1999)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Hoojung Chung
    • 1
  • Hae-Chang Rim
    • 1
  1. 1.Department of Computer ScienceKorea UniversitySeoulKorea

Personalised recommendations