Document (#2651)

Author
Robertson, S.E.
Title
On term selection for query expansion
Source
Journal of documentation. 46(1990) no.4, S.359-364
Year
1990
Abstract
In the framework of a relevance feedback system, term values or term weights may be used to (a) select new terms for inclusion in a query, and/or (b) weight the terms for retrieval purposes once selected. It has sometimes been assumed that the same weighting formula should be used for both purposes. This paper sketches a quantitative argument which suggests that the two purposes require different weighting formulae
Theme
Semantisches Umfeld in Indexierung u. Retrieval

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