Evaluation Tests of Information Retrieval Systems Available to Purchase

Thirty years or more ago, a favoured question in examination papers for librarians was some variation on the theme ‘Compare the merits of a classified catalogue and an alphabetical subject catalogue’. This was a subject which it was possible to write on or to discuss at great length, advancing a number of theoretical arguments or opinions expressed by pundits, without ever stating a single demonstrable fact. When, in the early 1950's, various people, such as Taube and Mooers, proposed new techniques for indexing, the reaction from the traditionally‐minded was such that it appeared there was to be a repetition of all the old arguments. In an editorial in American Documentation in 1955, Perry expressed a viewpoint, shared by many others, when he wrote: