Search-based class discretization

  • Luís Torgo
  • João Gama
Part II: Regular Papers
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1224)


We present a methodology that enables the use of classification algorithms on regression tasks. We implement this method in system RECLA that transforms a regression problem into a classification one and then uses an existent classification system to solve this new problem. The transformation consists of mapping a continuous variable into an ordinal variable by grouping its values into an appropriate set of intervals. We use misclassification costs as a means to reflect the implicit ordering among the ordinal values of the new variable. We describe a set of alternative discretization methods and, based on our experimental results, justify the need for a search-based approach to choose the best method. Our experimental results confirm the validity of our search-based approach to class discretization, and reveal the accuracy benefits of adding misclassification costs.


Regression Classification Discretization methods 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • Luís Torgo
    • 1
  • João Gama
    • 1
  1. 1.LIACC - University of PortoPortoPortugal

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