The TESTING OF INDEX LANGUAGE DEVICES

Abstract

The evaluation of information retrieval systems has recently become an important matter. In the past, however, most reports or proposals on this type of work appear largely to have ignored the efficiency of operation of the central core of an IR system, namely those operations concerned in the compilation and use of the index. The only aspects to receive consideration are the physical form of the index and the design of thesauri or classifications. The former activity has been slanted towards the use of computers and has tended to assume that this type of equipment will, ipso facto, give an improved performance but has made no attempt to justify cost factors which may be one hundred times that of conventional techniques. Work on thesauri and classifications, where it has been practical in nature, appears to consist of compiling lists of terms which go out of favour as quickly as any list of subject headings in the past; the more popular theoretical approach is the setting up of models or the use of increasingly abstruse and complex algebras. From the results and conclusions of the experimental work at Cranfield, it would seem that many of these investigations are comparatively trivial.