Understanding and Improving the Exemplar-based Generation for Open-domain Conversation

Seungju Han, Beomsu Kim, Seokjun Seo, Enkhbayar Erdenee, Buru Chang


Abstract
Exemplar-based generative models for open-domain conversation produce responses based on the exemplars provided by the retriever, taking advantage of generative models and retrieval models. However, due to the one-to-many problem of the open-domain conversation, they often ignore the retrieved exemplars while generating responses or produce responses over-fitted to the retrieved exemplars. To address these advantages, we introduce a training method selecting exemplars that are semantically relevant to the gold response but lexically distanced from the gold response. In the training phase, our training method first uses the gold response instead of dialogue context as a query to select exemplars that are semantically relevant to the gold response. And then, it eliminates the exemplars that lexically resemble the gold responses to alleviate the dependency of the generative models on that exemplars. The remaining exemplars could be irrelevant to the given context since they are searched depending on the gold response. Thus, our training method further utilizes the relevance scores between the given context and the exemplars to penalize the irrelevant exemplars. Extensive experiments demonstrate that our proposed training method alleviates the drawbacks of the existing exemplar-based generative models and significantly improves the performance in terms of appropriateness and informativeness.
Anthology ID:
2022.nlp4convai-1.18
Volume:
Proceedings of the 4th Workshop on NLP for Conversational AI
Month:
May
Year:
2022
Address:
Dublin, Ireland
Editors:
Bing Liu, Alexandros Papangelis, Stefan Ultes, Abhinav Rastogi, Yun-Nung Chen, Georgios Spithourakis, Elnaz Nouri, Weiyan Shi
Venue:
NLP4ConvAI
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
218–230
Language:
URL:
https://aclanthology.org/2022.nlp4convai-1.18
DOI:
10.18653/v1/2022.nlp4convai-1.18
Bibkey:
Cite (ACL):
Seungju Han, Beomsu Kim, Seokjun Seo, Enkhbayar Erdenee, and Buru Chang. 2022. Understanding and Improving the Exemplar-based Generation for Open-domain Conversation. In Proceedings of the 4th Workshop on NLP for Conversational AI, pages 218–230, Dublin, Ireland. Association for Computational Linguistics.
Cite (Informal):
Understanding and Improving the Exemplar-based Generation for Open-domain Conversation (Han et al., NLP4ConvAI 2022)
Copy Citation:
PDF:
https://aclanthology.org/2022.nlp4convai-1.18.pdf
Video:
 https://aclanthology.org/2022.nlp4convai-1.18.mp4
Code
 hyperconnect/corge