PTB Graph Parsing with Tree Approximation

Yoshihide Kato, Shigeki Matsubara


Abstract
The Penn Treebank (PTB) represents syntactic structures as graphs due to nonlocal dependencies. This paper proposes a method that approximates PTB graph-structured representations by trees. By our approximation method, we can reduce nonlocal dependency identification and constituency parsing into single tree-based parsing. An experimental result demonstrates that our approximation method with an off-the-shelf tree-based constituency parser significantly outperforms the previous methods in nonlocal dependency identification.
Anthology ID:
P19-1530
Volume:
Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics
Month:
July
Year:
2019
Address:
Florence, Italy
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
5344–5349
Language:
URL:
https://aclanthology.org/P19-1530
DOI:
10.18653/v1/P19-1530
Bibkey:
Copy Citation:
PDF:
https://aclanthology.org/P19-1530.pdf
Code
 yosihide/ptb2cf
Data
Penn Treebank