The Role of Neural Network Size in TRAP/HATS Feature Extraction

  • František Grézl
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6836)


We study the role of sizes of neural networks (NNs) in TRAP (TempoRAl Patterns) and HATS (Hidden Activation TRAPS architecture) probabilistic features extraction. The question of sufficient size of band NNs is linked with the question whether the Merger is able to compensate for lower accuracy of band NNs. For both architectures, the performance increases with increasing size of Merger NN. For TRAP architecture, it was observed, that increasing band NN size over some value has not further positive effect on final performance. The situation is different when HATS architecture is employed – increasing size of band NNs has mostly negative effect on final performance. This is caused by merger not being able to efficiently exploit the information hidden in its input with increased size. The solution is proposed in form of bottle-neck NN which allows for arbitrary size output.


Feature Extraction Speech Recognition Speech Signal Probabilistic Feature Word Error Rate 
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 2011

Authors and Affiliations

  • František Grézl
    • 1
  1. 1.Speech@FITBrno University of TechnologyCzech Republic

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