Large margin learning of Bayesian classifiers based on Gaussian mixture models

  • Authors:
  • Franz Pernkopf;Michael Wohlmayr

  • Affiliations:
  • Graz University of Technology, Graz, Austria;Graz University of Technology, Graz, Austria

  • Venue:
  • ECML PKDD'10 Proceedings of the 2010 European conference on Machine learning and knowledge discovery in databases: Part III
  • Year:
  • 2010

Quantified Score

Hi-index 0.00

Visualization

Abstract

We present a discriminative learning framework for Gaussian mixture models (GMMs) used for classification based on the extended Baum-Welch (EBW) algorithm [1]. We suggest two criteria for discriminative optimization, namely the class conditional likelihood (CL) and the maximization of the margin (MM). In the experiments, we present results for synthetic data, broad phonetic classification, and a remote sensing application. The experiments show that CL-optimized GMMs (CL-GMMs) achieve a lower performance compared to MM-optimized GMMs (MM-GMMs), whereas both discriminative GMMs (DGMMs) perform significantly better than generatively learned GMMs. We also show that the generative discriminatively parameterized GMM classifiers still allow to marginalize over missing features, a case where generative classifiers have an advantage over purely discriminative classifiers such as support vector machines or neural networks.