Describes a genetic algorithm (GA) that assigns weights to query terms in a ranked-output document retrieval system. Experiments showed the GA often found weights slightly superior to those produced by deterministic weighting (F4). Many times, however, the two methods gave the same results and sometimes the F4 results were superior, indicating…

The National Library of Medicine has discarded connect hour-only billing for a more equitable system, which distributes user costs by type and intensity of work performed and data delivered. User data (cost comparisons, interpolated input/output count per connect hours, connect hours per year) were analyzed and further improvements are planned.…

Proposes algorithmic method of searching and presents experimental data testing efficacy of using Boolean negation to eliminate redundancy and reduce cognitive strain of communication barrier at human-computer interface. Cognitive information processes, concept of Boolean NOT, and problem-solving behavior are explored. Twenty-five references are…

Describes preliminary investigation of the use of International Computers Limited's Distributed Array Processor (DAP) for parallel searching of large serial files of documents. DAP hardware and software, test collections, measurement of DAP performance, search algorithms, experimental results, and DAP suitability for interactive searching are…

Evaluates and compares two recently proposed automatic methods for relevance feedback of Boolean queries (Dillon method, which uses probabilistic approach as basis, and disjunctive normal form method). Conclusions are drawn concerning the use of effective feedback methods in a Boolean query environment. Nineteen references are included. (EJS)