Tuning as Ranking 论文

摘要

We offer a simple, effective, and scalable method for statistical machine translation pa-rameter tuning based on the pairwise approach to ranking (Herbrich et al., 1999). Unlike the popular MERT algorithm (Och, 2003), our pairwise ranking optimization (PRO) method is not limited to a handful of parameters and can easily handle systems with thousands of features. Moreover, unlike recent approaches built upon the MIRA algorithm of Crammer and Singer (2003) (Watanabe et al., 2007; Chi-ang et al., 2008b), PRO is easy to imple-ment. It uses off-the-shelf linear binary classi-fier software and can be built on top of an ex-isting MERT framework in a matter of hours. We establish PRO’s scalability and effective-ness by comparing it to MERT and MIRA and demonstrate parity on both phrase-based and syntax-based systems in a variety of language pairs, using large scale data scenarios. 1