Morphosyntactic Target Language Matching in Statistical Machine Translation
Simon Zwarts, Mark Dras · 2008
While the intuition that morphological pre-processing of languages in various applica-tions can be beneficial appears to be often true, especially in the case of morphologi-cally richer languages, it is not always the case. Previous work on translation between Nordic languages, including the morphologi-cally rich Finnish, found that morphological analysis and preprocessing actually led to a decrease in translation quality below that of the unprocessed baseline. In this paper we investigate the proposition that the effect on translation quality depends on the kind of morphological preprocessing; and in particular that a specific kind of mor-phological preprocessing before translation could improve translation quality, a prepro-cessing that first transforms the source lan-guage to look more like the target, adapted from work on preprocessing via syntactically motivated reordering. We show that this is in-deed the case in translating from Finnish, and that the results hold for different target lan-guages and different morphological analysers. 1