Multimodal Fact-Level Attribution for Verifiable Reasoning

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Wan, David, Wang, Han, Wang, Ziyang, Stengel-Eskin, Elias, Lee, Hyunji, Bansal, Mohit
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915988486750208
author Wan, David
Wang, Han
Wang, Ziyang
Stengel-Eskin, Elias
Lee, Hyunji
Bansal, Mohit
author_facet Wan, David
Wang, Han
Wang, Ziyang
Stengel-Eskin, Elias
Lee, Hyunji
Bansal, Mohit
contents Multimodal large language models (MLLMs) are increasingly used for real-world tasks involving multi-step reasoning and long-form generation, where reliability requires grounding model outputs in heterogeneous input sources and verifying individual factual claims. However, existing multimodal grounding benchmarks and evaluation methods focus on simplified, observation-based scenarios or limited modalities and fail to assess attribution in complex multimodal reasoning. We introduce MuRGAt (Multimodal Reasoning with Grounded Attribution), a benchmark for evaluating fact-level multimodal attribution in settings that require reasoning beyond direct observation. Given inputs spanning video, audio, and other modalities, MuRGAt requires models to generate answers with explicit reasoning and precise citations, where each citation specifies both modality and temporal segments. To enable reliable assessment, we introduce an automatic evaluation framework that strongly correlates with human judgments. Benchmarking with human and automated scores reveals that even strong MLLMs frequently hallucinate citations despite correct reasoning. Moreover, we observe a key trade-off: increasing reasoning depth or enforcing structured grounding often degrades accuracy, highlighting a significant gap between internal reasoning and verifiable attribution.
format Preprint
id arxiv_https___arxiv_org_abs_2602_11509
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Multimodal Fact-Level Attribution for Verifiable Reasoning
Wan, David
Wang, Han
Wang, Ziyang
Stengel-Eskin, Elias
Lee, Hyunji
Bansal, Mohit
Computation and Language
Artificial Intelligence
Computer Vision and Pattern Recognition
Multimodal large language models (MLLMs) are increasingly used for real-world tasks involving multi-step reasoning and long-form generation, where reliability requires grounding model outputs in heterogeneous input sources and verifying individual factual claims. However, existing multimodal grounding benchmarks and evaluation methods focus on simplified, observation-based scenarios or limited modalities and fail to assess attribution in complex multimodal reasoning. We introduce MuRGAt (Multimodal Reasoning with Grounded Attribution), a benchmark for evaluating fact-level multimodal attribution in settings that require reasoning beyond direct observation. Given inputs spanning video, audio, and other modalities, MuRGAt requires models to generate answers with explicit reasoning and precise citations, where each citation specifies both modality and temporal segments. To enable reliable assessment, we introduce an automatic evaluation framework that strongly correlates with human judgments. Benchmarking with human and automated scores reveals that even strong MLLMs frequently hallucinate citations despite correct reasoning. Moreover, we observe a key trade-off: increasing reasoning depth or enforcing structured grounding often degrades accuracy, highlighting a significant gap between internal reasoning and verifiable attribution.
title Multimodal Fact-Level Attribution for Verifiable Reasoning
topic Computation and Language
Artificial Intelligence
Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2602.11509