Leave No One Behind: Fairness-Aware Cross-Domain Recommender Systems for Non-Overlapping Users

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Chen, Weixin, Zhao, Yuhan, Chen, Li, Pan, Weike
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908462643937280
author Chen, Weixin
Zhao, Yuhan
Chen, Li
Pan, Weike
author_facet Chen, Weixin
Zhao, Yuhan
Chen, Li
Pan, Weike
contents Cross-domain recommendation (CDR) methods predominantly leverage overlapping users to transfer knowledge from a source domain to a target domain. However, through empirical studies, we uncover a critical bias inherent in these approaches: while overlapping users experience significant enhancements in recommendation quality, non-overlapping users benefit minimally and even face performance degradation. This unfairness may erode user trust, and, consequently, negatively impact business engagement and revenue. To address this issue, we propose a novel solution that generates virtual source-domain users for non-overlapping target-domain users. Our method utilizes a dual attention mechanism to discern similarities between overlapping and non-overlapping users, thereby synthesizing realistic virtual user embeddings. We further introduce a limiter component that ensures the generated virtual users align with real-data distributions while preserving each user's unique characteristics. Notably, our method is model-agnostic and can be seamlessly integrated into any CDR model. Comprehensive experiments conducted on three public datasets with five CDR baselines demonstrate that our method effectively mitigates the CDR non-overlapping user bias, without loss of overall accuracy. Our code is publicly available at https://github.com/WeixinChen98/VUG.
format Preprint
id arxiv_https___arxiv_org_abs_2507_17749
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Leave No One Behind: Fairness-Aware Cross-Domain Recommender Systems for Non-Overlapping Users
Chen, Weixin
Zhao, Yuhan
Chen, Li
Pan, Weike
Information Retrieval
Cross-domain recommendation (CDR) methods predominantly leverage overlapping users to transfer knowledge from a source domain to a target domain. However, through empirical studies, we uncover a critical bias inherent in these approaches: while overlapping users experience significant enhancements in recommendation quality, non-overlapping users benefit minimally and even face performance degradation. This unfairness may erode user trust, and, consequently, negatively impact business engagement and revenue. To address this issue, we propose a novel solution that generates virtual source-domain users for non-overlapping target-domain users. Our method utilizes a dual attention mechanism to discern similarities between overlapping and non-overlapping users, thereby synthesizing realistic virtual user embeddings. We further introduce a limiter component that ensures the generated virtual users align with real-data distributions while preserving each user's unique characteristics. Notably, our method is model-agnostic and can be seamlessly integrated into any CDR model. Comprehensive experiments conducted on three public datasets with five CDR baselines demonstrate that our method effectively mitigates the CDR non-overlapping user bias, without loss of overall accuracy. Our code is publicly available at https://github.com/WeixinChen98/VUG.
title Leave No One Behind: Fairness-Aware Cross-Domain Recommender Systems for Non-Overlapping Users
topic Information Retrieval
url https://arxiv.org/abs/2507.17749