Identifying contradictory and contrastive relations between statements to outline web information on a given topic

We present a method for producing a bird's-eye view of statements that are expressed on Web pages on a given topic. This method aggregates statements that are relevant to the topic, and shows contradictory and contrastive relations among them. This view of contradictions and contrasts helps users acquire a top-down understanding of the topic. To realize this, we extract such statements and relations, including cross-document implicit contrastive relations between statements, in an unsupervised manner. Our experimental results indicate the effectiveness of our approach.