Abstract
Restricted non-monotonicity has been shown beneficial for the projective arc-eager dependency parser in previous research, as posterior decisions can repair mistakes made in previous states due to the lack of information. In this paper, we propose a novel, fully non-monotonic transition system based on the non-projective Covington algorithm. As a non-monotonic system requires exploration of erroneous actions during the training process, we develop several non-monotonic variants of the recently defined dynamic oracle for the Covington parser, based on tight approximations of the loss. Experiments on datasets from the CoNLL-X and CoNLL-XI shared tasks show that a non-monotonic dynamic oracle outperforms the monotonic version in the majority of languages.- Anthology ID:
- P17-1027
- Volume:
- Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
- Month:
- July
- Year:
- 2017
- Address:
- Vancouver, Canada
- Editors:
- Regina Barzilay, Min-Yen Kan
- Venue:
- ACL
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 288–298
- Language:
- URL:
- https://aclanthology.org/P17-1027
- DOI:
- 10.18653/v1/P17-1027
- Cite (ACL):
- Daniel Fernández-González and Carlos Gómez-Rodríguez. 2017. A Full Non-Monotonic Transition System for Unrestricted Non-Projective Parsing. In Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 288–298, Vancouver, Canada. Association for Computational Linguistics.
- Cite (Informal):
- A Full Non-Monotonic Transition System for Unrestricted Non-Projective Parsing (Fernández-González & Gómez-Rodríguez, ACL 2017)
- PDF:
- https://preview.aclanthology.org/nschneid-patch-3/P17-1027.pdf