Deriving a Bilingual Lexicon for Cross Language Information Retrieval

In this paper we describe a systematic approach to derive a bilingual lexicon automatically from parallel corpora. Following this approach, a lexicon was derived from the English and Dutch version of the Agenda 21 corpus. With the lexicon and a part of the corpus that was not used to derive the lexicon, a bilingual retrieval environment was build. Recall and precision of monolingual (Dutch) retrieval was compared to recall and precision of bilingual (Dutchto -English) retrieval. An experiment was conducted with the help of eight naive users who formulated queries and judged the relevance of retrieved fragments. The experiment shows 78% precision and 51% relative recall of monolingual retrieval, against 67% precision and 82% relative recall of bilingual retrieval. Keywords: Lexical Acquisition, Parallel Corpora, Statistical Natural Language Processing, Cross Language Information Retrieval. 1 Introduction The recent enormous increase in the use of information from internet and cd-rom ..