Human-in-the-Loop Rule Discovery for Micropost Event Detection

Platforms such as Twitter are increasingly being used for real-world event detection. Recent work often leverages event-related keywords for training machine learning based event detection models. These approaches make strong assumptions on the distribution of the relevant microposts containing the keyword - referred to as the expectation - and use it as a posterior regularization parameter during model training. Such approaches are, however, limited by the informativeness of the keywords and by the accuracy of the expectation estimation for keywords. In this work, we introduce a human-in-the-loop approach to jointly discover informative rules for model training while estimating their expectation. Our approach iteratively leverages the crowd to estimate both rule-specific expectation and the disagreement between the crowd and the model in order to discover new rules that are most beneficial for model training. To identify such rules, we introduce a hybrid human-machine workflow that engages human workers in rule discovery through an interactive hypothesis creation and testing interface and leverages automatic methods for suggesting useful rules for human verification. We empirically demonstrate the merits of our approach, on multiple real-world datasets and show that our approach improves the state of the art by a margin of 25.63% in terms of AUC.