引而不用的引用:RAG 系统中的参数化溯源研究
Cited but Unused: Parametric Provenance in Retrieval-Augmented Generation
AI 导读
一项 arXiv 研究提出用反事实替换法测量检索增强生成(RAG)系统的引用溯源:将检索段落中的事实替换为虚假变体后重新查询模型。结果发现,在两个模型家族(其中一族含五个规模)上,1.2% 至 15.7% 的可引用声明来自参数化记忆而非检索内容,且该比例随模型规模上升;标准自然语言推理验证的效果与随机无异。作者指出检测器测量的是模型“知道什么”而非“用了什么”,将两者分离仍是未解问题。
正文 · 原文
Abstract:Retrieval-augmented generation systems attach citations to attribute claims to their sources. These citations frequently misstate provenance, and standard verification cannot detect this. We measure provenance by counterfactual value substitution: a fact in the retrieved passages is replaced with a false variant and the model re-queried. We find that across five sizes of one model family and a second comparator family, 1.2% to 15.7% of citable claims derive from parametric memory rather than the retrieved context. At the most conservative substitution distance these figures are 4.6% and 8.5% on the two models we tested at it, with the rate rising with model size within a family. We further find that natural language inference verification, the standard approach, gives results indistinguishable from chance across models, even when restricted to the cited passage. We determine that the cause is structural: a model answering from memory selects a citation that agrees with its output. Comparing ten attribution methods on identical claims, the contrast between the model's distribution with and without context best separates provenance. Acting on that signal does not improve provenance honesty at these base rates. The resulting detector is hence still not accurate enough to act on: it measures what the model knew rather than what it used, and separating those remains the open problem.
| Subjects: | Artificial Intelligence (cs.AI) |
| Cite as: | arXiv:2611.17161 [cs.AI] |
| (or arXiv:2611.17161v1 [cs.AI] for this version) | |
| https://doi.org/10.48550/arXiv.2611.17161 arXiv-issued DOI via DataCite (pending registration) |
Submission history
From: Tanzeel Abbas Mr [view email]
[v1]
Thu, 12 Nov 2026 17:39:14 UTC (65 KB)
来源:arXiv cs.AI · arxiv.org