Logic-Scaffolding: Personalized Aspect-Instructed Recommendation Explanation Generation using LLMs
Behnam Rahdari, Hao Ding, Ziwei Fan, Yifei Ma, Zhuotong Chen, Anoop Deoras, Branislav Kveton
TL;DR
The paper tackles the challenge of producing personalized, reliable explanations for recommendations with LLMs. It introduces Logic-Scaffolding, which coordinates relevant-item selection, aspect extraction via few-shot prompts, and chain-of-thought reasoning to generate explanations with intermediate reasoning steps. Empirical evaluation on MovieLens 1M with Falcon-40b demonstrates superior ratings on relevance, readability, factuality, and proper utterance compared to a zero-shot baseline, with statistically significant improvements and large effect sizes. This work advances practical, transparent personalization in explainable recommender systems by enabling domain-aligned aspects and structured reasoning within LLM-based explanations.
Abstract
The unique capabilities of Large Language Models (LLMs), such as the natural language text generation ability, position them as strong candidates for providing explanation for recommendations. However, despite the size of the LLM, most existing models struggle to produce zero-shot explanations reliably. To address this issue, we propose a framework called Logic-Scaffolding, that combines the ideas of aspect-based explanation and chain-of-thought prompting to generate explanations through intermediate reasoning steps. In this paper, we share our experience in building the framework and present an interactive demonstration for exploring our results.
