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Understanding inverse document frequency: on theoretical arguments for IDF

Robertson, Stephen·2004·Journal of Documentation

Abstract

The term weighting function known as IDF was proposed in 1972, and has since been extremely widely used, usually as part of a TF*IDF function. It is often described as a heuristic, and many papers have been written (some based on Shannon’s Information Theory) seeking to establish some theoretical basis for it. Some of these attempts are reviewed, and it is shown that the Information Theory approaches are problematic, but that there are good theoretical justifications of both IDF and TF*IDF in traditional probabilistic model of information retrieval.

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Metadata

Authors
Robertson, S.
Venue
Journal of Documentation
Publisher
Emerald
Published
2004-10
Volume
60
Issue
5
Pages
503-520
ISSN
0022-0418 (ISSN-L)
OpenAlex
W2024932032
Cited by
1,541
References
24
FWCI
42.72
Type
journal article
Language
en
Open access
closed

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CoChat. (2026). Citation check: Understanding inverse document frequency: on theoretical arguments for IDF. https://app.cochat.ai/papers/10.1108/00220410410560582
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Robertson, S. (2004). Understanding inverse document frequency: on theoretical arguments for IDF. Journal of Documentation. https://doi.org/10.1108/00220410410560582

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