arXiv cs.CL· Puyuan Yang, Shaoxuan Dong, Liujie Wu, Xiaochun Cheng, Bo Li·· 12 小时前AI 评分38
事实正确但立场偏颇：RAG 中的立场投毒与证据平衡
Factual Yet One-Sided: Stance Poisoning and Evidence Balancing in Retrieval-Augmented Generation
AI 导读
研究发现，当注入后 ProCon 文档的平均主题级投毒占比达 18.9% 时，来自不同厂商的四款生成模型均出现与投毒方向一致的立场偏移，且偏移随四个集中度水平单调上升。
正文
Abstract:The stance expressed in responses from retrieval-augmented generation systems is significantly influenced by the stance distribution of the retrieved materials. Existing research on knowledge poisoning has primarily targeted factual errors. In contrast, this study focuses on injection attacks in which the facts are correct but the stance on a controversial issue is one-sided. At a mean topic-level poisoning share of 18.9% within the post-injection ProCon documents, all four generation models from different vendors exhibited stance shifts aligned with the poisoning direction; across four concentration levels, the shifts increased monotonically.
This paper proposes a Stance-Balancing Middleware positioned between the retriever and the generator. It consists of stance detection, fixed balancing (2 supporting + 2 opposing + 1 neutral), and a debiasing prompt, without introducing additional large language model calls. Across all eight concentration-direction settings, the complete method reduced the magnitude of stance deviation by an estimated 0.106 to 0.350; the six settings at poisoning shares of 11.9%-18.9% remained significant after Holm adjustment (adjusted p <= 0.009). In the cross-model experiment, all eight model-direction combinations moved along the stance axis in the corrective direction, and seven of eight showed a clearly detected reduction in absolute distance from 0. In the concentration sweep, the post-defense intervals included 0 in all eight settings, while the cross-model pro-poisoning results retained small positive residual point estimates of +0.045 to +0.063. For 20 candidate documents, stance detection took approximately 1.5% of the median generation time on a single GPU and approximately 16% on CPU.
| Comments: | 29 pages, 4 figures, 20 tables |
| Subjects: | Computation and Language (cs.CL); Cryptography and Security (cs.CR); Information Retrieval (cs.IR) |
| Cite as: | arXiv:2610.34294 [cs.CL] |
| (or arXiv:2610.34294v1 [cs.CL] for this version) | |
| https://doi.org/10.48550/arXiv.2610.34294 arXiv-issued DOI via DataCite (pending registration) |
Submission history
From: Puyuan Yang [view email]
[v1]
Sun, 25 Oct 2026 13:50:10 UTC (1,445 KB)
来源：arXiv cs.CL · arxiv.org