SCA: Improving Document Grounded Response Generation based on Supervised Cross-Attention

Hyeongjun Choi, Seung-Hoon Na, Beomseok Hong, Youngsub Han, Byoung-Ki Jeon

http://doi.org/10.5626/JOK.2024.51.4.326

Document-grounded response generation is the task of aiming at generating conversational responses by “grounding” the factual evidence on task-specific domain, such as consumer consultation or insurance planning, where the evidence is obtained from the retrieved relevant documents in response to a user’s question under the current dialogue context. In this study, we propose supervised cross-attention (SCA) to enhance the ability of the response generation model to find and incorporate “response-salient snippets” (i.e., spans or contents), which are parts of the retrieved document that should be included and maintained in the actual answer generation. SCA utilizes the additional supervised loss that focuses cross-attention weights on the response-salient snippets, and this attention supervision likely enables a decoder to effectively generate a response in a “saliency-grounding” manner, by strongly attending to the important parts in the retrieved document. Experiment results on MultiDoc2Dial show that the use of SCA and additional performance improvement methods leads to the increase of 1.13 in F1 metric over the existing SOTA, and reveals that SCA leads to the increase of 0.25 in F1.