The traditional concern with relevance or nonrelevance of unexamined documents is misplaced, and traditional measures of effectiveness should be replaced by estimates of direct utility of examined documents. (Author)

Presents results from study of mathematical models (Cobb-Douglas model, mixture of Poissons, inverse effects of distance, weighted entropy) relating to usage of information systems, and notes papers developed during study which provide three types of analysis--literature reviews, analytical studies, and tests of models. Six references are…

Argues that the best strategy for building integrated, personalized information systems consists of linguistically oriented knowledge and inference, rather than artificial intelligence techniques. The discussion addresses difficulties in the evaluation of such systems and strategies for devising performance studies. (five references) (CLB)

Describes information system being developed by Unesco's General Information Program and Brazilian Institute for Information Science and Technology to overcome lack of timely, relevant data to support national information decision making. Principles and examples of practical applications of the system are presented. Prospects and requirements for…