使用共指消解增强多轮任务型对话生成

指代是一种重要的语言现象,运用指代可以避免复杂的词语在句子中重复出现,使语句简洁连贯。在多轮口语对话中,使用代词指代实体可以提高沟通的效率,然而,对话中频繁出现的代词给计算机语言理解增加了难度,进而影响了机器生成回复的质量。该文提出通过消解代词提高对话生成质量,先通过端到端的共指消解模型识别出多轮对话中蕴含的表述同一实体的所有代词和名词短语,即指代簇(coreference clusters);然后使用两种不同的方法,利用指代簇信息增强对话模型: ①使用指代簇信息恢复问句的完整语义,以降低机器语言理解的难度; ②使用图卷积神经网络将指代簇信息编码融入对话生成模型,以提高机器理解对话的能力。该文所提的两个方法在RiSAWOZ公开数据集上进行了验证,实验结果表明,两个方法均可以显著提升对话生成的性能。

Improving Multi-turn Task-oriented Dialogue Generation Using Coreference Resolution

Coreference is a common and essential language phenomenon. With coreference, repeated occurrence of complex expressions can be avoided in sentences, which makes sentences concise and coherent. In multi-turn spoken dialogue, the use of pronouns referring to entities can enhance communication efficiency. However, highly-frequent use of pronouns in a dialogue would make it difficult for machine to understand utterances, which in turn affects the quality of machine-generated responses. This article suggests that the quality of dialogue generation can be improved by resolving pronouns, specifically, to identify all the pronouns and noun phrases that express the same entity contained in multi-turn dialogue through coreference resolution model which is defined as coreference clusters. Two different methods are proposed and applied to coreference cluster to improve the dialogue model: (1)Using coreference clusters to recover the complete semantics of a query in order to reduce the difficulty of machine language understanding; (2)Using graph convolutional network to encode the coreference clusters into dialogue model which can improve the language understanding ability of the model. The proposed two methods in this article are tested onRiSAWOZ, a large-scale public dialogue dataset. The experimental results show that both methods can significantly improve the performance of dialogue generation.