The logic of different types of weighting are discussed, and experiments testing weighting schemes of these types are described. The results show that one type of weighting leads to material performance improvements in quite different collection environments. (22 references) (Author)

A proposal for a computer-aided method of building up an indexing language is made. The method involves linking terms relevant to any special retrieval system into the UDC, via a video terminal, producing a hybrid thesaurus-classification. (5 references)

Reports on a series of programs that have been developed to process data bases, consisting of textual items, and to index and arrange (classify) the data items in accordance with an automatically generated classification system. (Author)

Goffman's indirect method and a MeSH tree structure were used to classify a set of 109 medical documents. (PF)

The concept of tri-citation is introduced, as a logical extension of co-citation, and a geometrical model (the circle) is devised to account for these and all other forms of multiple citation. (Author)

A system of automatic indexing based on Baye's theorem is described briefly. (18 references) (Author)

Heuristic methods for the construction of term classes are presented and experimental results are obtained to illustrate the usefulness of the method. (Author/PF)

An automatic classification technique has been developed, based on the character structure of words. (Author)

An automatic classification technique using patterns formed by citations in document bibliographies was found to give 62 percent precision and 45 percent recall in a sample file of physics documents. (PF)

Retrieval performance with automatic term classifications for three test collections has been variable. This paper attempts to discover why. The real difference between the collections is in the separation of relevant from non-relevant documents. The separation is so poor that classification cannot be expected to succeed. (14 references)…