Discusses the inability of the standard Boolean logic model of information retrieval to deal effectively with the inherent fallibility of retrieval decisions. Recent advances in information retrieval research are reviewed, and their practical potential for overcoming the deficiencies of the Boolean model is examined. (45 references) (Author/CLB)

A theoretical framework used to derive a weighting mechanism for ranking output documents in Boolean retrieval systems is described in detail. A simple illustrative example is included, and the implications of such an approach are discussed. (64 references) (Author/CLB)