Statistical Machine Translation: Little Changes Big Impacts

In this paper we describe some experiments carried out to test the impact of automatic casing and punctuation changes when training and testing statistical translation models. The experiments described here concern the translation from/to English and Brazilian Portuguese texts but since the superficial changes investigated are language independent, we believe that the conclusions can be applied to many other pairs of languages. These experiments were designed aiming at setting a baseline scenario for future training and testing of more complex statistical translation models such as the factored ones. From the experiments presented here it is possible to see that case and punctuation changes have a significant impact on automatic translation results.