An Algorithm for Segmenting Categorical Time Series into Meaningful Episodes

  • Paul Cohen
  • Niall Adams
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2189)

Abstract

This paper describes an unsupervised algorithm for segmenting categorical time series. The algorithm first collects statistics about the frequency and boundary entropy of ngrams, then passes a window over the series and has two “expert methods” decide where in the window boundaries should be drawn. The algorithm segments text into words successfully in three languages. We claim that the algorithm finds meaningful episodes in categorical time series, because it exploits two statistical characteristics of meaningful episodes.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Paul Cohen
    • 1
  • Niall Adams
    • 2
  1. 1.Department of Computer ScienceUniversity of MassachusettsUSA
  2. 2.Department of MathematicsImperial CollegeLondon

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