Paper: Asynchronous Binarization for Synchronous Grammars

ACL ID P09-2036
Title Asynchronous Binarization for Synchronous Grammars
Venue Annual Meeting of the Association of Computational Linguistics
Session Short Paper
Year 2009

Binarization of n-ary rules is critical for the effi- ciencyofsyntacticmachinetranslationdecoding. Because the target side of a rule will generally reorder the source side, it is complex (and some- times impossible) to find synchronous rule bina- rizations. However, we show that synchronous binarizations are not necessary in a two-stage de- coder. Instead, the grammar can be binarized one way for the parsing stage, then rebinarized in a different way for the reranking stage. Each indi- vidual binarization considers only one monolin- gual projection of the grammar, entirely avoid- ing the constraints of synchronous binarization and allowing binarizations thatare separately op- timized for each stage. Compared to n-ary for- est reranking, even simple target-side binariza- tion schemes improv...