This
new meta training set is then used to train the meta classifier which learns to
predict the final class. So for the additional cost of running an appropriate meta
classifier it is possible to utilize all the output generated by a crossvalidation.
Furthermore, the dimensionality of the meta dataset is equal to the number of
classes multiplied by the number of base classifiers3 and thus fairly independent
of the dimensionality of the original dataset. The additional training cost for
the meta classifier is usually much smaller than the training costs for the base
classifiers, especially for large, high-dimensional datasets