Paper: Soft Cross-lingual Syntax Projection for Dependency Parsing

ACL ID C14-1075
Title Soft Cross-lingual Syntax Projection for Dependency Parsing
Venue International Conference on Computational Linguistics
Session Main Conference
Year 2014

This paper proposes a simple yet effective framework of soft cross-lingual syntax projection to transfer syntactic structures from source language to target language using monolingual treebanks and large-scale bilingual parallel text. Here, soft means that we only project reliable dependencies to compose high-quality target structures. The projected instances are then used as additional training data to improve the performance of supervised parsers. The major issues for this idea are 1) errors from the source-language parser and unsupervised word aligner; 2) intrinsic syntactic non-isomorphism between languages; 3) incomplete parse trees after projection. To handle the first two issues, we propose to use a probabilistic dependency parser trained on the target-language treebank, and prune o...