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Showing papers on "Ranking (information retrieval) published in 1975"




Journal ArticleDOI
TL;DR: The accuracy and cost‐effectiveness of the automatically‐assigned subject headings and classifications has been compared with that of the manual system and the results were encouraging and the costs comparable to those of a manual system.
Abstract: A number of techniques have been studied for the automatic assignment of controlled subject headings and classifications from free indexing. These techniques involve the automatic manipulation and truncation of the free‐index phrases assigned to a document and the use of a manually‐constructed thesaurus and automatically‐generated dictionaries together with statistical ranking and weighting methods. These are based on the use of a statistically‐generated ‘adhesion coefficient’ which reflects the degree of association between the free‐indexing terms, the controlled subject headings, and the classifications. By the analysis of a large sample of manually‐indexed documents the system generates dictionaries of free‐language and controlled‐language terms together with their associated classifications and adhesion coefficients. Having learnt from the manually‐indexed documents the system uses these dictionaries in the subsequent automatic classification procedure. The accuracy and cost‐effectiveness of the automatically‐assigned subject headings and classifications has been compared with that of the manual system. The results were encouraging and the costs comparable to those of a manual system.

36 citations


Journal ArticleDOI
TL;DR: This note describes a method that uses the vertex ranking approach in conjunction with procedures that resolve difficulties involving degeneracy and inequality constraints when one attempts to implement Murty's method directly.
Abstract: Murty has suggested that the linear fixed-charge problem can be solved by ranking the vertices of the polyhedral constraint set according to their continuous objective values and then adding the fixed charges to determine an optimal solution. Several problems involving degeneracy and inequality constraints arise when one attempts to implement Murty's method directly. This note describes a method that uses the vertex ranking approach in conjunction with procedures that resolve these difficulties. We also give computational results.

30 citations


Journal ArticleDOI
TL;DR: The worst possible method to assess the relevance of documents is a mere bisection into relevant and irrelevant, and even an ideal system cannot consistently find all relevant documents and only those, which is empirically well known.
Abstract: When assessing the relevance of documents, different jurors usually do not completely agree. A simple model is set up to take this fact into account by assuming that the relevance assigned by the juror is a random variable. It leads to some interesting conclusions: The worst possible method to assess the relevance is a mere bisection into relevant and irrelevant. Even an ideal system cannot consistently find all relevant documents and only those, which is empirically well known. The retrieval system should also assign a measure of relevance rather than divide the set of all documents only into those found and those not found; in particular, Boolean operations should be supplemented by a ranking algorithm.

13 citations






Patent
06 Nov 1975

1 citations