Papers › Does RAG Introduce Unfairness in LLMs? Evaluating Fairness in Retrieval-Augmented...

Does RAG Introduce Unfairness in LLMs? Evaluating Fairness in Retrieval-Augmented Generation Systems

29 Sep 2024arXiv:2409.19804archive 2025-07-28

Xuyang Wu, Shuowei Li, Hsin-Tai Wu, Zhiqiang Tao, Yi Fang

Retrieval-Augmented Generation (RAG) has recently gained significant attention for its enhanced ability to integrate external knowledge sources into open-domain question answering (QA) tasks. However, it remains unclear how these models address fairness concerns, particularly with respect to sensitive attributes such as gender, geographic location, and other demographic factors. First, as language models evolve to prioritize utility, like improving exact match accuracy, fairness considerations may have been largely overlooked. Second, the complex, multi-component architecture of RAG methods poses challenges in identifying and mitigating biases, as each component is optimized for distinct objectives. In this paper, we aim to empirically evaluate fairness in several RAG methods. We propose a fairness evaluation framework tailored to RAG, using scenario-based questions and analyzing disparities across demographic attributes. Our experimental results indicate that, despite recent advances in utility-driven optimization, fairness issues persist in both the retrieval and generation stages. These findings underscore the need for targeted interventions to address fairness concerns throughout the RAG pipeline. The dataset and code used in this study are publicly available at this GitHub Repository https://github.com/elviswxy/RAG_fairness .

PaperPDFCodeCode Syntology ran

In Syntology Open this paper in Syntology's Atlas, the map of the papers in Syntology's graph and their citations.

For agents, Syntology's MCP tool lists every function and class Syntology harvested from this paper and whether it ran (how to connect): get_harvested_code_for_paper(arxiv_id="2409.19804")

Code

Syntology Ran 8 of 10 code samples harvested from 1 repository linked to this paper; 2 have no recorded run. Of those that ran: 1 ran · our draft was wrong; 1 ran · fixture could not drive it; 6 ran with no contract checked.

By repository: official repository: 10 samples from 1 repository, 8 ran. The run record, sample by sample. “Ran” means executed on a synthesized input, not that the code is correct or reproduces the paper.

elviswxy/rag_fairness officialmentioned in paperpytorch report

Repository list and official/mentioned flags are the archive's, frozen 2025-07-28. Reachability, where shown, is from one Syntology probe window (2026-09-16 to 2026-09-18); repositories not probed show nothing. GitHub stars are not tracked.

Code Syntology ran Syntology

10 samples harvested; 8 ran; 0 honoured the contract we drafted; 2 have no recorded run. Read from Syntology's graph 2026-09-24; that is when this build read the record, not when the samples ran.

1ran · our draft was wrong
1ran · fixture could not drive it
6ran
2unverified

Licence: 10 of the 10 samples are pointer only, meaning Syntology does not serve that copy's text. This page shows no code text for any sample; each one links to its file in the repository.

Harvested from elviswxy/rag_fairness. “Ran” means the sample executed on a synthesized input. It does not mean the output is correct, and nothing here reproduces the paper's results. “Honoured” and “violated” refer to a contract Syntology drafted from the code itself; “our draft was wrong” and “fixture could not drive it” are failures of Syntology's instrument, not of the code.

Each sample ends with its code_sha256, Syntology's identity for that exact code. An agent fetches the stored sample with Syntology's MCP tool get_code(code_sha256="…") (how to connect); click an identity to copy that call.

Repository labels, per sample. official repository: The archive marks this repository official for the paper. named in the paper: The archive records that the paper mentions this repository; it is not marked official. community (archive-listed): In the archive's code links for this paper, not marked official and not recorded as mentioned in the paper. found in paper text by Syntology: Syntology found this repository in the paper's own text; whether it is the authors' implementation is not asserted. community: Not in the archive's code links for this paper; a community repository Syntology harvested. Samples from a repository marked official are listed first. Licence labels name the repository's licence as recorded at harvest. “Pointer only” means Syntology does not serve that copy's text, for one of four reasons: no licence file was found; the licence was not identified; the licence is recorded as permissive but that copy's record is not marked cleared; or the licence is outside the permissive list Syntology serves text under (MIT, Apache-2.0, BSD and similar). Some licences outside that list permit redistribution, such as WTFPL, and GPL-3.0 under its conditions; they are simply not on the list. Hover a licence label for the reason. File links open the file on GitHub at the default branch, which may have changed since the harvest.

basic_process elviswxy/rag_fairness/preprocess_trec_wiki.py official repository ran no licence file found · pointer only · b645135617451850 · report
compute_bleu elviswxy/rag_fairness/flashrag/evaluator/_bleu.py official repository ran no licence file found · pointer only · 2dd8e40379d7bbb9 · report
cross_attention_forward elviswxy/rag_fairness/flashrag/generator/fid.py official repository ran · fixture could not drive it no licence file found · pointer only · 6bef6bdd6eb44070 · report
gender_random_all_irrelevant_pairs_by_q_text elviswxy/rag_fairness/prepare_rag_fairness_data.py official repository ran no licence file found · pointer only · 1c191093e712cd32 · report
gender_random_all_relevant_pairs_by_q_text elviswxy/rag_fairness/prepare_rag_fairness_data.py official repository ran no licence file found · pointer only · 573b1bed7e8e5370 · report
gender_random_one_relevant_pairs_by_q_text elviswxy/rag_fairness/prepare_rag_fairness_data.py official repository ran no licence file found · pointer only · 74ed96cc94ee5e21 · report
get_existed_results elviswxy/rag_fairness/offline_evaluation.py official repository ran fingerprinted no licence file found · pointer only · a0df218ea7171bde · report
normalize_answer elviswxy/rag_fairness/flashrag/evaluator/utils.py official repository ran · our draft was wrong fingerprinted no licence file found · pointer only · dae7ab386661a4f4 · report
create_segments elviswxy/rag_fairness/preprocess_trec_wiki.py official repository unverified no licence file found · pointer only · 71b1ede1102f38f1 · report
load_corpus elviswxy/rag_fairness/preprocess_trec_wiki.py official repository unverified no licence file found · pointer only · 7b7eafb43497dd26 · report

Tasks

FairnessOpen-Domain Question AnsweringQuestion AnsweringRAGRetrievalRetrieval-augmented Generation

Results from the paper archive 2025-07-28

No leaderboard rows for this paper in the archive.

Methods

AdamAttentionAttention DropoutBARTBERTBPEDense ConnectionsDropoutLayer NormalizationLinear LayerLinear Warmup With Linear DecayMulti-Head AttentionRAGResidual ConnectionSoftmaxWeight DecayWordPiece

Report a problem or propose a change · a person checks every report against the paper or source before anything changes; decisions are listed on /corrections