Smaller Self-indexes for Natural Language

  • Nieves R. Brisaboa
  • Gonzalo Navarro
  • Alberto Ordóñez
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7608)


Self-indexes for natural-language texts, where these are regarded as token (word or separator) sequences, achieve very attractive space and search time. However, they suffer from a space penalty due to their large vocabulary. In this paper we show that by replacing the Huffman encoding they implicitly use by the slightly weaker Hu-Tucker encoding, which respects the lexical order of the vocabulary, both their space and time are improved.


Text Collection Natural Language Text Wavelet Tree Large Alphabet Source Code Repository 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Nieves R. Brisaboa
    • 1
  • Gonzalo Navarro
    • 2
  • Alberto Ordóñez
    • 1
  1. 1.Database Lab.Univ. of A CoruñaSpain
  2. 2.Dept. of Computer ScienceUniv. of ChileChile

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