Analyzes recent developments in the problem of processing queries expressed as Boolean expressions, shows that the concept of threshold values resolves the problems inherent with relevance weights, and explores possible evaluation mechanisms for document retrieval based on fuzzy set theory. Sixteen references are listed. (FM)

Examines through a series of mathematical models (theorems, descriptions, and examples), properties and operations on inverted files, which are used in an information retrieval system based on thesaurus with weighted descriptors. (CWM)

Applies theories about organizational information processing to better understand the influences on method of access and on effects of using online information. Explores the extent to which organizational differences also influence these variables, what the positive and negative outcomes from using online commercial databases are, and how those…

Analyzes the use of weights to denote a query representation and/or the indexing of a document as a generalization of a Boolean retrieval system. Criteria are given for the functions used to evaluate the relevance of the records to a specific query and a new evaluation approach is suggested. (CWM)

Presents a new method of document retrieval based on the fundamental operations of fuzzy set theory. Basic notions are introduced. Then the syntax and semantics of the proposed language for document retrieval is given, and an algorithm allocating documents to particular queries is described and its properties are discussed. (Author/CWM)

Presents a relational logical model to support a sophisticated document retrieval system in which flexible forms of inferential and associative searching can be performed, and provides examples of ad hoc inquiries. Several problems of particular importance to document retrieval are discussed in terms of this model. (27 references) (Author/CLB)