Discusses term position as a search tactic in Boolean retrieval systems and describes ranked output systems that have used term weighting. The use of term proximity devices in ranked output systems is proposed, the algorithms used are explained, and a search experiment with a test collection is described. (19 references) (LRW)

Reviews recent research into the use of hierarchic agglomerative clustering methods for document retrieval. The topics discussed include the calculation of interdocument similarities, algorithms used to implement clustering methods on large databases, validity testing of document hierarchies, appropriate search strategies, and other applications…

In machine learning there is considerable interest in techniques which improve planning ability. Initial investigations have identified a wide variety of techniques to address this issue. Progress has been hampered by the utility problem, a basic tradeoff between the benefit of learned knowledge and the cost to locate and apply relevant knowledge.…