Improving LLM-powered Recommendations with Personalized Information
Jiahao Liu, Xueshuo Yan, Dongsheng Li, Guangping Zhang, Hansu Gu, Peng Zhang, Tun Lu, Li Shang, Ning Gu
TL;DR
This paper tackles the underutilization of LLM reasoning in recommender systems by introducing CoT-Rec, a two-stage pipeline that injects Chain-of-Thought processes—user preference analysis and item perception analysis—into LLM-powered recommendations. It combines a CRM-based retrieval stage (CRM-as-Retriever) with an LLM-based ranking stage (LLM-as-Ranker), and shows how explicit personalized information extraction and utilization improve both retrieval accuracy and ranking robustness, including reduced position bias. The approach is model-agnostic, scalable (operations in extraction are offline), and employs techniques like Encode & Map embeddings, role-playing item perception, and LoRA-tuned ranking. Experimental results on three datasets demonstrate meaningful gains across retrieval and ranking, with publicly available code, highlighting practical potential for industrial deployment.
Abstract
Due to the lack of explicit reasoning modeling, existing LLM-powered recommendations fail to leverage LLMs' reasoning capabilities effectively. In this paper, we propose a pipeline called CoT-Rec, which integrates two key Chain-of-Thought (CoT) processes -- user preference analysis and item perception analysis -- into LLM-powered recommendations, thereby enhancing the utilization of LLMs' reasoning abilities. CoT-Rec consists of two stages: (1) personalized information extraction, where user preferences and item perception are extracted, and (2) personalized information utilization, where this information is incorporated into the LLM-powered recommendation process. Experimental results demonstrate that CoT-Rec shows potential for improving LLM-powered recommendations. The implementation is publicly available at https://github.com/jhliu0807/CoT-Rec.
