Improving Low-Resource Morphological Inflection via Self-Supervised Objectives

Adam Wiemerslage, Katharina Von Der Wense


Abstract
Self-supervised objectives have driven major advances in NLP by leveraging large-scale unlabeled data, but such resources are scarce for many of the world’s languages. Surprisingly, they have not been explored much for character-level tasks, where smaller amounts of data have the potential to be beneficial. We investigate the effectiveness of self-supervised auxiliary tasks for morphological inflection – a character-level task highly relevant for language documentation – in extremely low-resource settings, training encoder-decoder transformers for 19 languages and 13 auxiliary objectives. Autoencoding yields the best performance when unlabeled data is very limited, while character masked language modeling (CMLM) becomes more effective as data availability increases. Though objectives with stronger inductive biases influence model predictions intuitively, they rarely outperform standard CMLM. However, sampling masks based on known morpheme boundaries consistently improves performance, highlighting a promising direction for low-resource morphological modeling.
Anthology ID:
2025.acl-long.1195
Volume:
Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
July
Year:
2025
Address:
Vienna, Austria
Editors:
Wanxiang Che, Joyce Nabende, Ekaterina Shutova, Mohammad Taher Pilehvar
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
24494–24510
Language:
URL:
https://preview.aclanthology.org/ingestion-acl-25/2025.acl-long.1195/
DOI:
Bibkey:
Cite (ACL):
Adam Wiemerslage and Katharina Von Der Wense. 2025. Improving Low-Resource Morphological Inflection via Self-Supervised Objectives. In Proceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 24494–24510, Vienna, Austria. Association for Computational Linguistics.
Cite (Informal):
Improving Low-Resource Morphological Inflection via Self-Supervised Objectives (Wiemerslage & Wense, ACL 2025)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingestion-acl-25/2025.acl-long.1195.pdf