TY - JOUR AB - 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 the traditional probabilistic model of information retrieval. VL - 60 IS - 5 SN - 0022-0418 DO - 10.1108/00220410410560582 UR - https://doi.org/10.1108/00220410410560582 AU - Robertson Stephen PY - 2004 Y1 - 2004/01/01 TI - Understanding inverse document frequency: on theoretical arguments for IDF T2 - Journal of Documentation PB - Emerald Group Publishing Limited SP - 503 EP - 520 Y2 - 2024/04/25 ER -