Multilingual domain modeling in Twenty-One: automatic creation of a bi-directional translation lexicon from a parallel corpus
Djoerd Hiemstra · 1998
Within the project Twenty-One, which aims at effective dissemination of information on ecology and sustainable development, a system is developed that supports cross-language information retrieval for any of the four languages Dutch, English, French and German. Knowledge of this application domain is neededto enhanceexisting translation resourcesfor the purpose of lexical disambiguation. This paper describes an algorithm for the automated acquisition of a translation lexicon from a parallel corpus. New about the presented algorithm is the statistical language model used. Because the algorithm is based on a symmetric translation model it becomespossible to identify one-to-many and many-to-one relations between words of a language pair. We claim that the presented method has two advantagesover algorithms that have been published before. Firstly, because the translation model is more powerful, the resulting bilingual lexicon will be more accurate. Secondly, the resulting bilingual lexicon can be used to translate in both directions between a language pair. Different versions of the algorithm were evaluated on the Dutch and English version of the Agenda 21 corpus, which is a UN document on the application domain of sustainable development. 1