Classification by Multilayer Feedforward Ensembles
As shown in the bibliography, training an ensemble of networks is an interesting way to improve the performance with respect to a single network. However there are several methods to construct the ensemble and there are no complete results showing which one could be the most appropriate. In this paper we present a comparison of eleven different methods. We have trained ensembles of 3, 9, 20 and 40 networks to show results in a wide spectrum of values. The results show that the improvement in performance above 9 networks in the ensemble depends on the method but it is usually marginal. Also, the best method is called ”Decorrelated” and uses a penalty term in the usual Backpropagation function to decorrelate the network outputs in the ensemble.
KeywordsPenalty Term Ensemble Method Error Reduction Training Pattern Training Point
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