Document (#33021)

Author

Xu, J.
Weischedel, R.

Title

Empirical studies on the impact of lexical resources on CLIR performance

Source

Information processing and management. 41(2005) no.3, S.475-488

Year

2005

Abstract

In this paper, we compile and review several experiments measuring cross-lingual information retrieval (CLIR) performance as a function of the following resources: bilingual term lists, parallel corpora, machine translation (MT), and stemmers. Our CLIR system uses a simple probabilistic language model; the studies used TREC test corpora over Chinese, Spanish and Arabic. Our findings include: One can achieve an acceptable CLIR performance using only a bilingual term list (70-80% on Chinese and Arabic corpora). However, if a bilingual term list and parallel corpora are available, CLIR performance can rival monolingual performance. If no parallel corpus is available, pseudo-parallel texts produced by an MT system can partially overcome the lack of parallel text. While stemming is useful normally, with a very large parallel corpus for Arabic-English, stemming hurt performance in our empirical studies with Arabic, a highly inflected language.

Theme

Multilinguale Probleme

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