Paper: Excitatory or Inhibitory: A New Semantic Orientation Extracts Contradiction and Causality from the Web

ACL ID D12-1057
Title Excitatory or Inhibitory: A New Semantic Orientation Extracts Contradiction and Causality from the Web
Venue Conference on Empirical Methods in Natural Language Processing
Session Main Conference
Year 2012
Authors

We propose a new semantic orientation, Ex- citation, and its automatic acquisition method. Excitation is a semantic property of predicates that classifies them into excitatory, inhibitory and neutral. We show that Excitation is useful for extracting contradiction pairs (e.g., destroy cancer ? develop cancer) and causality pairs (e.g., increase in crime ? heighten anxiety). Our experiments show that with automatically acquired Excitation knowledge we can extract one million contradiction pairs and 500,000 causality pairs with about 70% precision from a 600 million page Web corpus. Furthermore, by combining these extracted causality and contradiction pairs, we can generate one mil- lion plausible causality hypotheses that are not written in any single sentence in our corpus with reasonable p...