Italian and Spanish Null Subjects. A Case Study Evaluation in an MT Perspective.
Lorenza Russo, Sharid Loáiciga, Asheesh Gulati · 2012
Thanks to their rich morphology, Italian and Spanish allow pro-drop pronouns, i.e., non lexically-realized subject pronouns.Here we distinguish between two different types of null subjects: personal pro-drop and impersonal pro-drop.We evaluate the translation of these two categories into French, a non pro-drop language, using Its-2, a transfer-based system developed at our laboratory; and Moses, a statistical system.Three different corpora are used: two subsets of the Europarl corpus and a third corpus built using newspaper articles.Null subjects turn out to be quantitatively important in all three corpora, but their distribution varies depending on the language and the text genre though.From a MT perspective, translation results are determined by the type of pro-drop and the pair of languages involved.Impersonal pro-drop is harder to translate than personal pro-drop, especially for the translation from Italian into French, and a significant portion of incorrect translations consists of missing pronouns.