Prof. F. Pernkopf, Graz University of Technology

Lecture
                              VORTRAG
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Oesterreichisches Forschungsinstitut fuer Artificial Intelligence (OFAI)                   
Freyung 6/6, A-1010 Wien
Tel.: +43-1-5336112-19, Fax: +43-1-5336112-77, Email: sec@ofai.at


Prof. Dr. Franz Pernkopf
Signal Proc. & Speech Communication Lab
Graz University of Technology


"Discriminative Learning of Bayesian Network Classifiers"


We present a maximum margin parameter learning algorithm 
for Bayesian network classifiers using the conjugate gradient
algorithm for optimization. Unlike previous approaches, we 
maintain the normalization constraint of the conditional 
probabilities during optimization and the probabilistic 
interpretation is not lost. 
This enables marginalization over missing features in our 
discriminatively optimized Bayesian network, a case where 
generative classifiers have an advantage over discriminative 
classifiers. 

In the experiments, we show that maximizing the margin 
dominates the conditional likelihood approach with respect 
to classification performance and is superior to generative
maximum likelihood estimation. 

Furthermore, empirical results are provided for the missing 
feature case.


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Time: Wednesday, 10th November 2010, 18:30 sharp

Location: Oesterreichisches Forschungsinstitut
fuer Artificial Intelligence, OFAI
Freyung 6, Stiege 6, 1010 Wien.


OESTERREICHISCHES FORSCHUNGSINSTITUT
FUER ARTIFICIAL INTELLIGENCE

Univ.-Prof. Ing. Dr. Robert Trappl

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