Abstract. In Machine Learning, ensembles are combination of classifiers. Their objective is to improve the accuracy. In previous works, we have presented a method for the generation of ensembles, named rotation-based. It transforms the training data set; it groups, randomly, the attributes in different subgroups, and applies, for each group, an axis rotation. If the used method for the induction of the classifiers is not invariant to rotations in the data set, the generated classifiers can be very different. In this way, different classifiers can be obtained (and combined) using the same induction method. The bias-variance decomposition of the error is used to get some insight into the behaviour of a classifier. It has been used to explain the success of ensemble learning techniques. In this work the bias and variance for the presented and other ensemble methods are calculated and used for comparison purposes.
Juan José Rodríguez, Carlos J. Alons