Document (#2650)

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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