A beam-search extraction algorithm for comparable data

This paper extends previous work on extracting parallel sentence pairs from comparable data (Munteanu and Marcu, 2005). For a given source sentence S, a maximum entropy (ME) classifier is applied to a large set of candidate target translations. A beam-search algorithm is used to abandon target sentences as non-parallel early on during classification if they fall outside the beam. This way, our novel algorithm avoids any document-level pre-filtering step. The algorithm increases the number of extracted parallel sentence pairs significantly, which leads to a BLEU improvement of about 1 % on our Spanish-English data. © 2009 ACL and AFNLP.