The Impact of Word Normalization Methods and Merging Strategies on Multilingual IR

  • Eija Airio
  • Heikki Keskustalo
  • Turid Hedlund
  • Ari Pirkola
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3237)


This article deals with both multilingual and bilingual IR. The source language is English, and the target languages are English, German, Finnish, Swedish, Dutch, French, Italian and Spanish. The approach of separate indexes is followed, and four different merging strategies are tested. Two of the merging methods are classical basic methods: the Raw Score method and the Round Robin method. Two simple new merging methods were created: the Dataset Size Based method and the Score Difference Based method. Two kinds of indexing methods are tested: morphological analysis and stemming. Morphologically analyzed indexes perform a slightly better than stemmed indexes. The merging method based on the dataset size performs best.


Average Precision Dataset Size Source Language Separate Index Merging Method 
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.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Eija Airio
    • 1
  • Heikki Keskustalo
    • 1
  • Turid Hedlund
    • 1
  • Ari Pirkola
    • 1
  1. 1.Department of Information StudiesUniversity of TampereFinland

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