User Simulator Assisted Open-ended Conversational Recommendation System

Qiusi Zhan, Xiaojie Guo, Heng Ji, Lingfei Wu


Abstract
Conversational recommendation systems (CRS) have gained popularity in e-commerce as they can recommend items during user interactions. However, current open-ended CRS have limited recommendation performance due to their short-sighted training process, which only predicts one utterance at a time without considering its future impact. To address this, we propose a User Simulator (US) that communicates with the CRS using natural language based on given user preferences, enabling long-term reinforcement learning. We also introduce a framework that uses reinforcement learning (RL) with two novel rewards, i.e., recommendation and conversation rewards, to train the CRS. This approach considers the long-term goals and improves both the conversation and recommendation performance of the CRS. Our experiments show that our proposed framework improves the recall of recommendations by almost 100%. Moreover, human evaluation demonstrates the superiority of our framework in enhancing the informativeness of generated utterances.
Anthology ID:
2023.nlp4convai-1.8
Volume:
Proceedings of the 5th Workshop on NLP for Conversational AI (NLP4ConvAI 2023)
Month:
July
Year:
2023
Address:
Toronto, Canada
Editors:
Yun-Nung Chen, Abhinav Rastogi
Venue:
NLP4ConvAI
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
89–101
Language:
URL:
https://aclanthology.org/2023.nlp4convai-1.8
DOI:
10.18653/v1/2023.nlp4convai-1.8
Bibkey:
Cite (ACL):
Qiusi Zhan, Xiaojie Guo, Heng Ji, and Lingfei Wu. 2023. User Simulator Assisted Open-ended Conversational Recommendation System. In Proceedings of the 5th Workshop on NLP for Conversational AI (NLP4ConvAI 2023), pages 89–101, Toronto, Canada. Association for Computational Linguistics.
Cite (Informal):
User Simulator Assisted Open-ended Conversational Recommendation System (Zhan et al., NLP4ConvAI 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.nlp4convai-1.8.pdf