Breaking the subtopic barrier in cross-document event coreference resolution

Cross-document event coreference resolution (CDCR) is the task of detecting and clustering mentions of events across a set of documents. A major bottleneck in CDCR is a lack of appropriate datasets, which stems from the difficulty of annotating data for this task. We present the first scalable approach for annotating cross-subtopic event coreference links, a highly valuable but rarely occurring type of cross-document link. The annotation of these links requires combing through hundreds of documents - an endeavor for which conventional token-level annotation schemes with trained expert annotators are too expensive. We instead propose crowdsourcing annotation on sentence level to achieve scalability.