research-article

Interpreting TF-IDF term weights as making relevance decisions

Authors:

Robert Wing Pong Luk,

Kui Lam KwokAuthors Info & Claims

ACM Transactions on Information Systems (TOIS), Volume 26, Issue 3

Article No.: 13, Pages 1 - 37

https://doi.org/10.1145/1361684.1361686

Published: 20 June 2008 Publication History

Abstract

A novel probabilistic retrieval model is presented. It forms a basis to interpret the TF-IDF term weights as making relevance decisions. It simulates the local relevance decision-making for every location of a document, and combines all of these “local” relevance decisions as the “document-wide” relevance decision for the document. The significance of interpreting TF-IDF in this way is the potential to: (1) establish a unifying perspective about information retrieval as relevance decision-making; and (2) develop advanced TF-IDF-related term weights for future elaborate retrieval models. Our novel retrieval model is simplified to a basic ranking formula that directly corresponds to the TF-IDF term weights. In general, we show that the term-frequency factor of the ranking formula can be rendered into different term-frequency factors of existing retrieval systems. In the basic ranking formula, the remaining quantity - log p(r¯|t ∈ d) is interpreted as the probability of randomly picking a nonrelevant usage (denoted by r¯) of term t. Mathematically, we show that this quantity can be approximated by the inverse document-frequency (IDF). Empirically, we show that this quantity is related to IDF, using four reference TREC ad hoc retrieval data collections.

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Index Terms

Interpreting TF-IDF term weights as making relevance decisions
1. Information systems
  1. Information retrieval
    1. Retrieval models and ranking

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cover image ACM Transactions on Information Systems

ACM Transactions on Information Systems Volume 26, Issue 3

June 2008

236 pages

ISSN:1046-8188

EISSN:1558-2868

DOI:10.1145/1361684

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Publication History

Published: 20 June 2008

Accepted: 01 September 2007

Revised: 01 July 2007

Received: 01 August 2004

Published in TOIS Volume 26, Issue 3

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