摘要
隐式篇章关系分类是浅层篇章结构分析(Shallow Discourse Parsing)中的子任务,也是自然语言处理(Natural Language Processing,NLP)中的一项重要任务。隐式篇章关系是由篇章关系中的论元对推理出来的逻辑语义关系。隐式篇章关系的分析结果可以应用于许多自然语言处理任务中,如机器翻译、自动文档摘要、问答系统等。针对隐式篇章关系分类任务,提出一种基于自注意力机制和句法信息的方法。通过双向长短时记忆网络(Bidirectional Long Short-Term Memory Network)对输入的结合句法信息的论元对进行建模,将论元对表示成低维稠密的向量;通过自注意力机制对论元对信息进行筛选。在PDTB2.0数据集上进行实验,结果表明该方法较基准系统获得了更好的效果。
Implicit discourse relation classification is a sub-task in shallow discourse parsing,and it's also an important task in natural language processing(NLP).Implicit discourse relation is a logic semantic relation inferred from the argument pairsin discourse relations.The analytical results of the implicit discourse relationship can be applied to many na-tural language processing tasks,such as machine translation,automatic document summarization,and question answe-ring system.This paper proposed a method based on self-attention mechanism and syntactic information for the classification task of implicit discourse relations.In this method,Bidirectional Long Short-Term Memory Network(BiLSTM) is used to model the inputted argument pairs with syntactic information and express the argument pairs into low-dimension dense vectors.The argument pair information was screened by the self-attention mechanism.At last,this paper conducted experiments on PDTB2.0 dataset.The experimental results show that the proposed model achieves better effects than the baseline system.
引文
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