Feature selection forcing overtraining may help to improve performance

One of the main drawbacks of machine learning systems is the negative effect caused by overtraining. If the points in the dataset are perfectly fitted, the generalization performance is usually bad. We propose to take profit of overtraining, together with Feature Selection, to improve the performance of a learning system. The main idea lies in the hypothesis that when the dataset is as fitted as possible, the system is forced to use all the available variables as much as possible. Noisy and useless variables can be detected if generalization improves when the system is not allowed to use them. Forcing overtraining, noisy and useless variables should be more outstanding. In order to test this hypothesis, we performed several Feature Selection experiments using Feedforward Neural Networks. The particular Feature Selection procedure used was Sequential Backward Selection. Experimental results with several real-world problems suggest that our hypothesis seems to be well-founded. Ironically, forcing overtraining may help to achieve good performance.