2021 年 28 巻 4 号 p. 1184-1209
We constructed a high-quality open-domain dialogue generation model called Anna that is composed of a hierarchical self-attention network with multiple convolution filters and a topic-augmented network. During daily conversations, humans typically respond by understanding a dialogue history and assembling their knowledge regarding the topic. However, existing dialogue generation models are weak at capturing the dependencies among words or utterances, resulting in an insufficient understanding of context and the generation of irrelevant responses. Previous works have largely ignored topic information modeling in multi-turn dialogue, making responses overly generic. Although pre-training using large-scale transformer models has recently resulted in enhanced performance, large parameter sizes complicate such models. Anna effectively captures contextual dependencies and assigns greater weight to important words and utterances to compute context representations. We incorporate topic information into our model as prior knowledge to synthesize topic representations. Two types of representations jointly determine the probability distributions of responses, which effectively simulates how people behave in real conversations. Empirical studies on both Chinese and English corpora demonstrate that Anna outperforms baseline models in terms of response quality, parameter size and decoding speed.