Asking Clarifying Questions for Preference Elicitation With Large Language Models
Ali Montazeralghaem, Guy Tennenholtz, Craig Boutilier, Ofer Meshi
TL;DR
This work tackles eliciting user preferences in conversational recommendations when user history is sparse. It introduces a diffusion-inspired two-stage framework that forward-corrupts a complete user profile by sequentially asking and removing information and then reverses this process by training an LLM to reconstruct the profile through effective clarifying questions, producing a funnel dialogue. The method relies on two LLMs, a Questioner and a User Simulator, and leverages Sequential Question Answering to generate training data that guides domain-general funnel questioning; experiments on Movielens show significant gains in elicitation quality (BLEU/ROUGE) and demonstrate a clear shift from broad to detailed questions. The results highlight the importance of fine-tuning and incorporating question history, offering a scalable approach to enhance preference elicitation across domains with LLMs.
Abstract
Large Language Models (LLMs) have made it possible for recommendation systems to interact with users in open-ended conversational interfaces. In order to personalize LLM responses, it is crucial to elicit user preferences, especially when there is limited user history. One way to get more information is to present clarifying questions to the user. However, generating effective sequential clarifying questions across various domains remains a challenge. To address this, we introduce a novel approach for training LLMs to ask sequential questions that reveal user preferences. Our method follows a two-stage process inspired by diffusion models. Starting from a user profile, the forward process generates clarifying questions to obtain answers and then removes those answers step by step, serving as a way to add ``noise'' to the user profile. The reverse process involves training a model to ``denoise'' the user profile by learning to ask effective clarifying questions. Our results show that our method significantly improves the LLM's proficiency in asking funnel questions and eliciting user preferences effectively.
