Multi-task learning in deep neural network for sentiment polarity and irony classification

We study the impact of a new multi-task learning approach in deep neural network for polarity and irony detection in Italian Twitter posts. We compare this approach with traditional single-task learning models. The different behavior of the two approaches shows the effectiveness of the proposed method that is able to combine the information from the two tasks improving the accuracy in both tasks. This is particularly true on edge cases in which knowledge about the two tasks is needed to classify a tweet, this is the case, for example, when the literal polarity of a tweet is inverted by irony.