Attention Weights as an Indicator: Analyzing and Improving Document Utilization in Retrieval-Augmented Generation

Jing Jin, Yuhan Song, Wen Luo, Houfeng Wang


Abstract
The generation of Retrieval-Augmented Generation (RAG) models is affected by factors such as the quality and order of input documents, indicating that their ability to utilize documents remains underdeveloped. This ability encompasses not only identifying useful documents from inputs but also minimizing positional bias and filtering irrelevant documents. To achieve this, key challenges include the model’s internal estimation of document importance and positional bias. In this paper, we conduct a comprehensive study on the properties of attention weights, examining the impact of factors like aggregation methods, document quality, document position, token type, and so on. Based on our findings, we propose strategies to enhance document utilization from three perspectives: document ranking, placement, and filtering. Comprehensive experiments show that our method outperforms baselines and improves document utilization effectiveness in a training-free manner.
Anthology ID:
2026.acl-long.1245
Volume:
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
27034–27052
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.1245/
DOI:
Bibkey:
Cite (ACL):
Jing Jin, Yuhan Song, Wen Luo, and Houfeng Wang. 2026. Attention Weights as an Indicator: Analyzing and Improving Document Utilization in Retrieval-Augmented Generation. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 27034–27052, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Attention Weights as an Indicator: Analyzing and Improving Document Utilization in Retrieval-Augmented Generation (Jin et al., ACL 2026)
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PDF:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.1245.pdf
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