Paper: A Comparison Of Syntactically Motivated Word Alignment Spaces

ACL ID E06-1019
Title A Comparison Of Syntactically Motivated Word Alignment Spaces
Venue Annual Meeting of The European Chapter of The Association of Computational Linguistics
Session Main Conference
Year 2006
Authors

This work is concerned with the space of alignments searched by word alignment systems. We focus on situations where word re-ordering is limited by syntax. We present two new alignment spaces that limit an ITG according to a given depen- dency parse. Weprovide D-ITGgrammars to search these spaces completely and without redundancy. We conduct a care- ful comparison of five alignment spaces, and show that limiting search with an ITG reduces error rate by 10%, while a D-ITG produces a 31% reduction.