Text Categorization and Semantic Browsing with Self-Organizing Maps on Non-euclidean Spaces

  • Jorg Ontrup
  • Helge Ritter
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2168)


This paper introduces a new type of Self-Organizing Map (SOM) for Text Categorization and Semantic Browsing. We propose a “hyperbolic SOM” (HSOM) based on a regular tesselation of the hyperbolic plane, which is a non-euclidean space characterized by constant negative gaussian curvature. This approach is motivated by the observation that hyperbolic spaces possess a geometry where the size of a neighborhood around a point increases exponentially and therefore provides more freedom to map a complex information space such as language into spatial relations. These theoretical findings are supported by our experiments, which show that hyperbolic SOMs can successfully be applied to text categorization and yield results comparable to other state-of-the-art methods. Furthermore we demonstrate that the HSOM is able to map large text collections in a semantically meaningful way and therefore allows a “semantic browsing” of text databases.


Hyperbolic Space Text Categorization Hyperbolic Plane Text Collection Prototype Vector 
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 2001

Authors and Affiliations

  • Jorg Ontrup
    • 1
  • Helge Ritter
    • 1
  1. 1.Neuroinformatics Group, Faculty of TechnologyBielefeld UniversityBielefeldGermany

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