Fully understanding narratives often requires identifying events in the context of whole documents and modeling the event relations. However, document-level event extraction is a challenging task as it requires the extraction of event and entity coreference, and capturing arguments that span across different sentences. Existing works on event extraction usually confine on extracting events from single sentences, which fail to capture the relationships between the event mentions at the scale of a document, as well as the event arguments that appear in a different sentence than the event trigger. In this paper, we propose an end-to-end model leveraging Deep Value Networks (DVN), a structured prediction algorithm, to efficiently capture cross-event dependencies for document-level event extraction. Experimental results show that our approach achieves comparable performance to CRF-based models on ACE05, while enjoys significantly higher computational efficiency.
翻译:充分理解叙事往往要求在整个文件范围内确定事件,并模拟事件关系;然而,文件级活动提取是一项艰巨的任务,因为它需要提取事件和实体的共通点,并捕捉跨越不同句子的论据;现有事件提取工作通常局限于从单句中提取事件,其中没有抓住文件规模中提到的事件之间的关系,以及出现在与事件触发器不同的句子中的事件论证;在本文件中,我们提议采用一个端到端模型,即利用深值网络(DVN),即结构化的预测算法,以有效捕捉文件级活动提取的跨事件依赖性;实验结果显示,我们的方法取得了与ACE05基于通用报告格式的模式相似的业绩,而计算效率则显著提高。