Leveraging Large Language Models in Conversational Recommender Systems
This work addresses the problem of building scalable and effective conversational recommender systems for users seeking personalized recommendations, but it is incremental as it builds on existing LLM capabilities.
The paper tackles the challenge of integrating Large Language Models (LLMs) into Conversational Recommender Systems (CRS) by proposing an end-to-end architecture with new implementations for user preference understanding, dialogue management, and explainable recommendations, and demonstrates RecLLM, a proof-of-concept system for YouTube videos built on LaMDA, showing fluency and diverse functionality.
A Conversational Recommender System (CRS) offers increased transparency and control to users by enabling them to engage with the system through a real-time multi-turn dialogue. Recently, Large Language Models (LLMs) have exhibited an unprecedented ability to converse naturally and incorporate world knowledge and common-sense reasoning into language understanding, unlocking the potential of this paradigm. However, effectively leveraging LLMs within a CRS introduces new technical challenges, including properly understanding and controlling a complex conversation and retrieving from external sources of information. These issues are exacerbated by a large, evolving item corpus and a lack of conversational data for training. In this paper, we provide a roadmap for building an end-to-end large-scale CRS using LLMs. In particular, we propose new implementations for user preference understanding, flexible dialogue management and explainable recommendations as part of an integrated architecture powered by LLMs. For improved personalization, we describe how an LLM can consume interpretable natural language user profiles and use them to modulate session-level context. To overcome conversational data limitations in the absence of an existing production CRS, we propose techniques for building a controllable LLM-based user simulator to generate synthetic conversations. As a proof of concept we introduce RecLLM, a large-scale CRS for YouTube videos built on LaMDA, and demonstrate its fluency and diverse functionality through some illustrative example conversations.