CAPTR: Caption-based Context Pruning for Multimodal Tabular Reasoning

Prasham Titiya, Leon Engländer, Gaurav Najpande, Tampu Ravi Kumar, Iryna Gurevych, Vivek Gupta


Abstract
Multimodal Large Language Models struggle with tabular reasoning on tables containing images as cells owing to their limited memory and the distractions posed by the surrounding irrelevant visual elements. Existing context-reduction methods reduce context size but degrade reasoning accuracy: text-only pruning neglects visual cells, token-level pruning discards valuable information, and retrieval cannot understand table structure. We propose CAPTR: Caption-based Context Pruning for Tabular Reasoning, a two-stage framework that uses image captions as a lightweight textual proxy to prune non-pertinent rows and columns and then restores images for reasoning. CAPTR can reduce the context length by 80% while achieving up to 8% accuracy improvement against competitive baselines. By analyzing the error cases, we find that entity confusion contributes to the majority of the remaining errors. CAPTR is the first multimodal context-reduction method to improve performance on multimodal tabular reasoning.
Anthology ID:
2026.emnlp-main.826
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
19189–19214
Language:
URL:
https://aclanthology.org/2026.emnlp-main.826/
DOI:
Bibkey:
Cite (ACL):
Prasham Titiya, Leon Engländer, Gaurav Najpande, Tampu Ravi Kumar, Iryna Gurevych, and Vivek Gupta. 2026. CAPTR: Caption-based Context Pruning for Multimodal Tabular Reasoning. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 19189–19214, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
CAPTR: Caption-based Context Pruning for Multimodal Tabular Reasoning (Titiya et al., EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-main.826.pdf