Arc-swift: A Novel Transition System for Dependency Parsing

Peng Qi, Christopher D. Manning


Abstract
Transition-based dependency parsers often need sequences of local shift and reduce operations to produce certain attachments. Correct individual decisions hence require global information about the sentence context and mistakes cause error propagation. This paper proposes a novel transition system, arc-swift, that enables direct attachments between tokens farther apart with a single transition. This allows the parser to leverage lexical information more directly in transition decisions. Hence, arc-swift can achieve significantly better performance with a very small beam size. Our parsers reduce error by 3.7–7.6% relative to those using existing transition systems on the Penn Treebank dependency parsing task and English Universal Dependencies.
Anthology ID:
P17-2018
Volume:
Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers)
Month:
July
Year:
2017
Address:
Vancouver, Canada
Editors:
Regina Barzilay, Min-Yen Kan
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
110–117
Language:
URL:
https://aclanthology.org/P17-2018
DOI:
10.18653/v1/P17-2018
Bibkey:
Cite (ACL):
Peng Qi and Christopher D. Manning. 2017. Arc-swift: A Novel Transition System for Dependency Parsing. In Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers), pages 110–117, Vancouver, Canada. Association for Computational Linguistics.
Cite (Informal):
Arc-swift: A Novel Transition System for Dependency Parsing (Qi & Manning, ACL 2017)
Copy Citation:
PDF:
https://preview.aclanthology.org/nschneid-patch-4/P17-2018.pdf
Video:
 https://preview.aclanthology.org/nschneid-patch-4/P17-2018.mp4
Code
 qipeng/arc-swift
Data
Universal Dependencies