Improving the Classification Performance of Liquid State Machines Based on the Separation Property

  • Emmanouil Hourdakis
  • Panos Trahanias
Part of the IFIP Advances in Information and Communication Technology book series (IFIPAICT, volume 363)


Liquid State Machines constitute a powerful computational tool for carrying out complex real time computations on continuous input streams. Their performance is based on two properties, approximation and separation. While the former depends on the selection of class functions for the readout maps, the latter needs to be evaluated for a particular liquid architecture. In the current paper we show how the Fisher’s Discriminant Ratio can be used to effectively measure the separation of a Liquid State Machine. This measure is then used as a fitness function in an evolutionary framework that searches for suitable liquid properties and architectures in order to optimize the performance of the trained readouts. Evaluation results demonstrate the effectiveness of the proposed approach.


Liquid State Machines Separation Fisher Discriminant Ratio 


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Copyright information

© International Federation for Information Processing 2011

Authors and Affiliations

  • Emmanouil Hourdakis
    • 1
  • Panos Trahanias
    • 1
  1. 1.Institute of Computer ScienceFoundation for Research and Technology – Hellas (FORTH)HeraklionGreece

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