An Author Verification Approach Based on Differential Features: Notebook for PAN at CLEF 2015

We describe the approach that we submitted to the 2015 PAN competition [7] for the author identification task. The task consists in determining if an unknown document was authored by the same author of a set of documents with the same author. We propose a machine learning approach based on a number of different features that characterize documents from widely different points of view. We construct non-overlapping groups of homogeneous features, use a random forest regressor for each features group, and combine the output of all regressors by their arithmetic mean. We train a different regressor for each language. Our approach achieved the first position in the final rank for the Spanish language.