Semantically-informed Hierarchical Event Modeling

Shubhashis Roy Dipta, Mehdi Rezaee, Francis Ferraro


Abstract
Prior work has shown that coupling sequential latent variable models with semantic ontological knowledge can improve the representational capabilities of event modeling approaches. In this work, we present a novel, doubly hierarchical, semi-supervised event modeling framework that provides structural hierarchy while also accounting for ontological hierarchy. Our approach consistsof multiple layers of structured latent variables, where each successive layer compresses and abstracts the previous layers. We guide this compression through the injection of structured ontological knowledge that is defined at the type level of events: importantly, our model allows for partial injection of semantic knowledge and it does not depend on observing instances at any particular level of the semantic ontology. Across two different datasets and four different evaluation metrics, we demonstrate that our approach is able to out-perform the previous state-of-the-art approaches by up to 8.5%, demonstrating the benefits of structured and semantic hierarchical knowledge for event modeling.
Anthology ID:
2023.starsem-1.31
Volume:
Proceedings of the 12th Joint Conference on Lexical and Computational Semantics (*SEM 2023)
Month:
July
Year:
2023
Address:
Toronto, Canada
Editors:
Alexis Palmer, Jose Camacho-collados
Venue:
*SEM
SIG:
SIGLEX
Publisher:
Association for Computational Linguistics
Note:
Pages:
353–369
Language:
URL:
https://aclanthology.org/2023.starsem-1.31
DOI:
10.18653/v1/2023.starsem-1.31
Bibkey:
Cite (ACL):
Shubhashis Roy Dipta, Mehdi Rezaee, and Francis Ferraro. 2023. Semantically-informed Hierarchical Event Modeling. In Proceedings of the 12th Joint Conference on Lexical and Computational Semantics (*SEM 2023), pages 353–369, Toronto, Canada. Association for Computational Linguistics.
Cite (Informal):
Semantically-informed Hierarchical Event Modeling (Roy Dipta et al., *SEM 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.starsem-1.31.pdf