English to Chinese Translation: How Chinese Character Matters

Word segmentation is helpful in Chinese nat-ural language processing in many aspects. However it is showed that different word seg-mentation strategies do not affect the per-formance of Statistical Machine Translation (SMT) from English to Chinese significant-ly. In addition, it will cause some confu-sions in the evaluation of English to Chinese SMT. So we make an empirical attempt to translation English to Chinese in the charac-ter level, in both the alignment model and lan-guage model. A series of empirical compari-son experiments have been conducted to show how different factors affect the performance of character-level English to Chinese SMT. We also apply the recent popular continuous s-pace language model into English to Chinese SMT. The best performance is obtained with the BLEU score 41.56, which improve base-line system (40.31) by around 1.2 BLEU s-core. Correspondence author. yThank all the reviewers for valuable comments and sug-