Deep dive into authorship verification of email messages with convolutional neural network

Authorship verification is the task of determining whether a specific individual did or did not write a text, which very naturally can be reduced to the binary-classification problem. This paper deals with the authorship verification of short email messages. Hereafter, we use “message” to identify the content of the information that is transmitted by email. The proposed method implements the binary classification with a sequence-to-sequence (seq2seq) model and trains a convolutional neural network (CNN) on positive (written by the “target” user) and negative (written by “someone else”) examples. The proposed method differs from previously published works, which represent text by numerous stylometric features, by requiring neither advanced text preprocessing nor explicit feature extraction. All messages are submitted to the CNN “as is,” after padding to the maximal length and replacing all words by their ID numbers. CNN learns the most appropriate features with backpropagation and then performs classification. The experiments performed on the Enron dataset using the TensorFlow framework show that the CNN classifier verifies message authorship very accurately.