A comparative study on generalizability of information extraction models on protest news

Information Extraction applications can help social scientists to obtain necessary information to understand the reasons behind certain social dynamics. Many recent state-of-the-art information extraction approaches are based on supervised machine learning which can recognize information that has similar patterns with previously shown ones. Recognizing relevant information with never-shown patterns, however, is still a challenging task. In this study, we design a Recurrent Neural Network (RNN) architecture employing ELMo embeddings and Residual Bidirectional Long-Short Term Memory layers to overcome this challenge in the context of CLEF 2019 ProtestNews shared task. Furthermore, we train a classical Conditional Random Fields (CRF) model as our strong baseline to display a contrast between a state-of-the-art classical machine learning approach and a recent neural network method both in performance and in generalizability. We show that RNN model outperforms classical CRF model and shows a better promise on generalizability.