Paper: A Simple and Effective Hierarchical Phrase Reordering Model

ACL ID D08-1089
Title A Simple and Effective Hierarchical Phrase Reordering Model
Venue Conference on Empirical Methods in Natural Language Processing
Session Main Conference
Year 2008

While phrase-based statistical machine trans- lation systems currently deliver state-of-the- art performance, they remain weak on word order changes. Current phrase reordering models can properly handle swaps between adjacent phrases, but they typically lack the ability to perform the kind of long-distance re- orderings possible with syntax-based systems. In this paper, we present a novel hierarchical phrase reordering model aimed at improving non-local reorderings, which seamlessly in- tegrates with a standard phrase-based system withlittlelossofcomputationalefficiency. We show that this model can successfully han- dle the key examples often used to motivate syntax-based systems, such as the rotation of a prepositional phrase around a noun phrase. We contrastour modelwith reordering model...