4arXiv cs.CL (Computation and Language)·
MEDIAREF: Public knowledge store for reproducible media background checks in LLM fact-checking
Researchers introduce MEDIAREF, a publicly available knowledge store of web-sourced documents covering 200 media sources, designed to enable reproducible and low-cost media background check (MBC) generation for automated fact-checking systems. The work addresses a gap in RAG-based fact-checking pipelines where retrieved evidence is assumed reliable but may be biased or outdated. The authors evaluate widely used LLMs on the MBC generation task and show MEDIAREF supports higher-quality outputs than proprietary search API alternatives. The contribution is primarily a dataset and methodology for source-critical reasoning in fact verification.
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MIRAGE: Training-free defense for RAG systems against misinformation in retrieved documents
Researchers introduce MIRAGE, a training-free, model-agnostic defense mechanism for long-form Retrieval-Augmented Generation systems exposed to polluted retrieval corpora. The system builds an NLI-based cross-document claim graph and uses a Defended-Claims Gate to either condition generation on consistently supported evidence or fall back to parametric answering. The authors also release a pollution benchmark protocol spanning four perturbation families and demonstrate that MIRAGE restores factuality across four long-form QA benchmarks where vanilla RAG degrades significantly. Code and datasets are publicly released.
Systematic study of LLM data referencing errors in tables, with lightweight critic model mitigation
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ProvenanceGuard: Source-aware factuality verification for MCP-based LLM agents
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