Modal Dependency Parsing as Structured Prediction over Source-Cue Scope

Jayeol Chun, Nianwen Xue


Abstract
Modal dependency parsing-the task of identifying a semantic graph that represents who is responsible for an event-centered claim and with what degree of certainty-relies on recognizing source-introducing cues and correctly linking them to their associated content. However, prior work has largely focused on identifying sources only, treating cue expressions and their modal coverage as auxiliary signals. In this work, we propose a structured prediction framework that leverages large language models (LLMs) to explicitly identify source-cue pairs as well as their respective scope, which together define the modal contexts governing downstream source attribution for events. By concentrating learning at the source-cue level and constraining event-level decisions to a small, scope-defined candidate set, our top-down approach enables more efficient inference in long, event-rich documents. Experiments show this approach surpasses prior state-of-the-art results by 3 and 4% for English and Chinese datasets, respectively.
Anthology ID:
2026.acl-long.1362
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:
29530–29540
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.1362/
DOI:
Bibkey:
Cite (ACL):
Jayeol Chun and Nianwen Xue. 2026. Modal Dependency Parsing as Structured Prediction over Source-Cue Scope. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 29530–29540, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Modal Dependency Parsing as Structured Prediction over Source-Cue Scope (Chun & Xue, ACL 2026)
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https://preview.aclanthology.org/ingest-acl/2026.acl-long.1362.pdf
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