Substructure Distribution Projection for Zero-Shot Cross-Lingual Dependency Parsing

Freda Shi, Kevin Gimpel, Karen Livescu


Abstract
We present substructure distribution projection (SubDP), a technique that projects a distribution over structures in one domain to another, by projecting substructure distributions separately. Models for the target domain can then be trained, using the projected distributions as soft silver labels. We evaluate SubDP on zero shot cross-lingual dependency parsing, taking dependency arcs as substructures: we project the predicted dependency arc distributions in the source language(s) to target language(s), and train a target language parser on the resulting distributions. Given an English tree bank as the only source of human supervision, SubDP achieves better unlabeled attachment score than all prior work on the Universal Dependencies v2.2 (Nivre et al., 2020) test set across eight diverse target languages, as well as the best labeled attachment score on six languages. In addition, SubDP improves zero shot cross-lingual dependency parsing with very few (e.g., 50) supervised bitext pairs, across a broader range of target languages.
Anthology ID:
2022.acl-long.452
Volume:
Proceedings of the 60th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
May
Year:
2022
Address:
Dublin, Ireland
Editors:
Smaranda Muresan, Preslav Nakov, Aline Villavicencio
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
6547–6563
Language:
URL:
https://aclanthology.org/2022.acl-long.452
DOI:
10.18653/v1/2022.acl-long.452
Bibkey:
Cite (ACL):
Freda Shi, Kevin Gimpel, and Karen Livescu. 2022. Substructure Distribution Projection for Zero-Shot Cross-Lingual Dependency Parsing. In Proceedings of the 60th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 6547–6563, Dublin, Ireland. Association for Computational Linguistics.
Cite (Informal):
Substructure Distribution Projection for Zero-Shot Cross-Lingual Dependency Parsing (Shi et al., ACL 2022)
Copy Citation:
PDF:
https://aclanthology.org/2022.acl-long.452.pdf
Software:
 2022.acl-long.452.software.zip
Data
Universal DependenciesWikiMatrix