Low-Cost Enrichment of Spanish WordNet with Automatically Translated Glosses: Combining General and Specialized Models

This paper studies the enrichment of Spanish WordNet with synset glosses automatically obtained from the English WordNet glosses using a phrase-based Statistical Machine Translation system. We construct the English-Spanish translation system from a parallel corpus of proceedings of the European Parliament, and study how to adapt statistical models to the domain of dictionary definitions. We build specialized language and translation models from a small set of parallel definitions and experiment with robust manners to combine them. A statistically significant increase in performance is obtained. The best system is finally used to generate a definition for all Spanish synsets, which are currently ready for a manual revision. As a complementary issue, we analyze the impact of the amount of in-domain data needed to improve a system trained entirely on out-of-domain data.