Large Language Models as Conversational Movie Recommenders: A User Study
Ruixuan Sun, Xinyi Li, Avinash Akella, Joseph A. Konstan
TL;DR
This paper investigates open-source Large Language Models as conversational movie recommenders through an online field study with 160 active users. It compares zero-shot, one-shot, and few-shot prompts across three scenarios to assess perceived quality, finding that LLMs excel at explainability and interaction but struggle with personalization, diversity, and trust, though they better surface niche recommendations. By analyzing both quantitative survey data and qualitative conversation patterns, the study shows that providing personal context and examples enhances recommendation quality, while longer dialogues can reduce satisfaction and that prompts alone do not substantially change outcomes. The work suggests design directions such as retrieval-augmented generation, grounding, multimodal data, and proactive user guidance to improve LLM-based recommender experiences and outlines actionable learnings for researchers and practitioners.
Abstract
This paper explores the effectiveness of using large language models (LLMs) for personalized movie recommendations from users' perspectives in an online field experiment. Our study involves a combination of between-subject prompt and historic consumption assessments, along with within-subject recommendation scenario evaluations. By examining conversation and survey response data from 160 active users, we find that LLMs offer strong recommendation explainability but lack overall personalization, diversity, and user trust. Our results also indicate that different personalized prompting techniques do not significantly affect user-perceived recommendation quality, but the number of movies a user has watched plays a more significant role. Furthermore, LLMs show a greater ability to recommend lesser-known or niche movies. Through qualitative analysis, we identify key conversational patterns linked to positive and negative user interaction experiences and conclude that providing personal context and examples is crucial for obtaining high-quality recommendations from LLMs.
