Cross-Language Text Retrieval With Three Languages

Michael L. Littman and Greg A. Keim

August 1997

Duke TR CS-1997-16

In cross-language text retrieval, query text objects in one language
are matched against a collection of text objects in another.  Previous
work showed that a two-language cross-language text-retrieval system
can be created completely automatically by a method called CL-LSI
trained on an aligned corpus of text objects.  In this paper, we look
at the challenge of creating a three-language cross-language
text-retrieval system.  We find that CL-LSI extends easily to the
three-language case when each training text object is available in all
three languages (3-way aligned corpora).  However, when each training
text object is supplied in only two of the three languages
(two-of-three pairwise aligned corpora), the natural extension of
CL-LSI behaves very badly.  We illustrate these observations on a
large English-French-Spanish collection and introduce analysis tools
that may be useful for future explorations.