Timeline extraction using distant supervision and joint inference

Savelie Cornegruta1 and Andreas Vlachos2
1King's College London, 2University of Sheffield


Abstract

In timeline extraction the goal is to order all the events in which a target entity is involved in a timeline. Due to the lack of explicitly annotated data, previous work is primarily rule-based and uses pre-trained temporal linking systems. In this work, we propose a distantly supervised approach by heuristically aligning timelines with documents. The noisy training data created allows us to learn models that anchor events to temporal expressions and entities; during testing, the predictions of these models are combined to produce the timeline. Furthermore, we show how to improve performance using joint inference. In experiments in the SemEval-2015 TimeLine task we show that our distantly supervised approach matches the state-of-the-art performance while joint inference further improves on it by 3.2 F-score points.