BEMEAE: Moving Beyond Exact Span Match for Event Argument Extraction

Enfa Fane, Md Nayem Uddin, Oghenevovwe Ikumariegbe, Daniyal Kashif, Eduardo Blanco, Steven Corman


Abstract
Event Argument Extraction (EAE) is a key task in natural language processing, focusing on identifying and classifying event arguments in text. However, the widely adopted exact span match (ESM) evaluation metric has notable limitations due to its rigid span constraints, often misidentifying valid predictions as errors and underestimating system performance. In this paper, we evaluate nine state-of-the-art EAE models on the RAMS and GENEVA datasets, highlighting ESM’s limitations. To address these issues, we introduce BEMEAE (Beyond Exact Span Match for Event Argument Extraction), a novel evaluation metric that recognizes predictions that are semantically equivalent to or improve upon the reference. BEMEAE integrates deterministic components with a semantic matching component for more accurate assessment. Our experiments demonstrate that BEMEAE aligns more closely with human judgments. We show that BEMEAE not only leads to higher F1 scores compared to ESM but also results in significant changes in model rankings, underscoring ESM’s inadequacy for comprehensive evaluation of EAE.
Anthology ID:
2025.naacl-long.295
Volume:
Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers)
Month:
April
Year:
2025
Address:
Albuquerque, New Mexico
Editors:
Luis Chiruzzo, Alan Ritter, Lu Wang
Venue:
NAACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
5734–5749
Language:
URL:
https://preview.aclanthology.org/moar-dois/2025.naacl-long.295/
DOI:
10.18653/v1/2025.naacl-long.295
Bibkey:
Cite (ACL):
Enfa Fane, Md Nayem Uddin, Oghenevovwe Ikumariegbe, Daniyal Kashif, Eduardo Blanco, and Steven Corman. 2025. BEMEAE: Moving Beyond Exact Span Match for Event Argument Extraction. In Proceedings of the 2025 Conference of the Nations of the Americas Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers), pages 5734–5749, Albuquerque, New Mexico. Association for Computational Linguistics.
Cite (Informal):
BEMEAE: Moving Beyond Exact Span Match for Event Argument Extraction (Fane et al., NAACL 2025)
Copy Citation:
PDF:
https://preview.aclanthology.org/moar-dois/2025.naacl-long.295.pdf