GOT4Rec: Graph of Thoughts for Sequential Recommendation
Zewen Long, Liang Wang, Shu Wu, Qiang Liu, Liang Wang
TL;DR
GOT4Rec tackles the challenge of leveraging external knowledge in sequential recommendation by introducing a graph of thoughts (GoT) that decomposes user reasoning into short-term, long-term, and collaborative components. It enables LLMs to generate and aggregate multiple thoughts through generation and aggregation transformations, guided by a multi-level retrieval module that uses embedding-based retrieval to refine candidate items. The approach achieves state-of-the-art results across three real-world datasets, with notable gains on food-related items due to effective short-term preference capture, and demonstrates improved novelty by reducing popularity bias. Overall, GOT4Rec provides a scalable, interpretable framework that combines rich user-sequence information with LLM reasoning to enhance recommendation quality and explainability.
Abstract
With their vast open-world knowledge and reasoning abilities, large language models (LLMs) have become a promising tool for sequential recommendation. Researchers have explored various methods to harness these capabilities, but most existing approaches rely on simple input-output prompting, failing to effectively bridge the gap between LLMs' general knowledge and the specific needs of recommendation tasks. While reasoning strategies like chain-of-thought (CoT) have been introduced to enhance performance, they often produce inaccurate recommendations due to underutilized user preference information and insufficient reasoning depth. To address these challenges, we propose GOT4Rec, a novel sequential recommendation method leveraging the graph of thoughts (GoT) reasoning strategy. Our method focuses on three key types of information in user histories: short-term interests, long-term interests and collaborative information from other users. It enables LLMs to reason independently and generate recommendations, subsequently aggregating results to derive final items. This method allows LLMs, with enhanced reasoning capabilities, to better utilize the user sequence information, producing more accurate recommendations and comprehensive explanations. Extensive experiments on real-world datasets demonstrate the effectiveness of GOT4Rec, outperforming existing state-of-the-art baselines with an average improvement of 37.11%. Our code is available at https://anonymous.4open.science/r/GOT4Rec.
