Retrieval-Augmented Recommendation Explanation Generation with Hierarchical Aggregation

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Sun, Bangcheng, Chen, Yazhe, Yang, Jilin, Li, Xiaodong, Li, Hui
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913939017695232
author Sun, Bangcheng
Chen, Yazhe
Yang, Jilin
Li, Xiaodong
Li, Hui
author_facet Sun, Bangcheng
Chen, Yazhe
Yang, Jilin
Li, Xiaodong
Li, Hui
contents Explainable Recommender System (ExRec) provides transparency to the recommendation process, increasing users' trust and boosting the operation of online services. With the rise of large language models (LLMs), whose extensive world knowledge and nuanced language understanding enable the generation of human-like, contextually grounded explanations, LLM-powered ExRec has gained great momentum. However, existing LLM-based ExRec models suffer from profile deviation and high retrieval overhead, hindering their deployment. To address these issues, we propose Retrieval-Augmented Recommendation Explanation Generation with Hierarchical Aggregation (REXHA). Specifically, we design a hierarchical aggregation based profiling module that comprehensively considers user and item review information, hierarchically summarizing and constructing holistic profiles. Furthermore, we introduce an efficient retrieval module using two types of pseudo-document queries to retrieve relevant reviews to enhance the generation of recommendation explanations, effectively reducing retrieval latency and improving the recall of relevant reviews. Extensive experiments demonstrate that our method outperforms existing approaches by up to 12.6% w.r.t. the explanation quality while achieving high retrieval efficiency.
format Preprint
id arxiv_https___arxiv_org_abs_2507_09188
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Retrieval-Augmented Recommendation Explanation Generation with Hierarchical Aggregation
Sun, Bangcheng
Chen, Yazhe
Yang, Jilin
Li, Xiaodong
Li, Hui
Information Retrieval
Explainable Recommender System (ExRec) provides transparency to the recommendation process, increasing users' trust and boosting the operation of online services. With the rise of large language models (LLMs), whose extensive world knowledge and nuanced language understanding enable the generation of human-like, contextually grounded explanations, LLM-powered ExRec has gained great momentum. However, existing LLM-based ExRec models suffer from profile deviation and high retrieval overhead, hindering their deployment. To address these issues, we propose Retrieval-Augmented Recommendation Explanation Generation with Hierarchical Aggregation (REXHA). Specifically, we design a hierarchical aggregation based profiling module that comprehensively considers user and item review information, hierarchically summarizing and constructing holistic profiles. Furthermore, we introduce an efficient retrieval module using two types of pseudo-document queries to retrieve relevant reviews to enhance the generation of recommendation explanations, effectively reducing retrieval latency and improving the recall of relevant reviews. Extensive experiments demonstrate that our method outperforms existing approaches by up to 12.6% w.r.t. the explanation quality while achieving high retrieval efficiency.
title Retrieval-Augmented Recommendation Explanation Generation with Hierarchical Aggregation
topic Information Retrieval
url https://arxiv.org/abs/2507.09188