Discusses several query-processing methods designed to allow the use of relevance weights or thresholds attached to terms and compares them with normal Boolean rules and fuzzy subset theory. Forty-five references are listed. (FM)

Describes the Waller-Kraft "wish list" of desired information retrieval system properties and identifies ambiguities caused by two distinct uses of the phrase "query term weight." Examples of problems arising from the ambiguity are given and a new list is created and discussed. (10 references) (Author/CLB)

Develops an approach for advance estimation of user charges based on information actually retrieved by searching numeric databases, and defines a method for query cardinality estimation. Based on the relational data model, which uses relational algebra, this method uses formal file descriptions to describe the database files. (LRW)

Presents a formal model for specification of logical requirements of computer-based information systems that incorporates structural and dynamic aspects based on two separate models: the Logical Information Processing Structure and the Logical Information Processing Network. The model's role in systems development is discussed. (MBR)

Calculations of storage requirements for retrieval systems using inverted files. Problem of minimal storage requirements for inverted file is solved for different index term distributions. (Author/KP)

Brief discussion of state-of-the-art of modeling complex information systems distinguishes between macrolevel and microlevel modeling of such systems. Network layout and hierarchical system models, simulation, information acquisition and dissemination, databases and information storage, and operating systems are described and assessed. Thirty-four…

Outlines an approach to the automatic construction of a knowledge base resulting in a system that is able in each phase of its construction to acquire domain knowledge from all new information that it is building, particularly index terms. Topics covered include production rules, the use of semantic networks, and user interfaces. (32 references)…

Five models which perform search tasks of the Data Base Access and Search Environment (DBASE) are presented and used for comparison with subject search performance--unconstrained (rule-based, decision theoretic) and constrained (optimal rule-based, rule-based, probabilistic rule-based). Previous experiments and the modeling approach are briefly…

Analyzes computer terminal memory performance in terms of overflow probability and average queueing delay, and presents new method to derive a closed expression for data arrivals with Erlangly distributed interarrival times and an approach to derive steady state probability expressions of the terminal memory content process. Twenty references are…

Describes an iterative method of document retrieval similar to relevance feedback in that user feedback is utilized in subsequent iterations. However, this method compares retrieved documents with each other using algebraic formulae which determine the boundaries of the area that contains descriptions of relevant documents. Fifteen references are…

Presents a dynamic model of user behavior when scanning an information storage and retrieval system output list, compares rules for determining the user's optimum stopping point, presents an algorithm for implementing the Bayesian model, and discusses implications for retrieval system design. Provided are 13 figures and 15 references. (Author/RBF)

Explores potential of mathematical theory of communication for information science and examines question of how to encode a message at time it is encountered for subsequent recall. Examples of problem, a prototype computer program and experiment, coding as embedding in associational nets, and nature of information are discussed. (Nine references.)…

Discusses methods of weighting of descriptors in document search patterns together with the concept of relative indexing and conditions which should be satisfied by descriptor weight. A procedure for modifiying document search patterns based on users' informational needs and opinions is outlined, and examples are given. Sixteen references are…

Presents an analytical approach to the interpretation of weighted Boolean queries. By distinguishing query term weights from query weights, a query becomes a means of describing classes of ideal documents and expressing relativity criteria among these descriptions. A formalization of query term weights is given in a fuzzy set theoretical context.…

Presents a system model for transmission of input data that is coming from terminals of users in a limited user resource-sharing environment. Performance of a mini/microcomputer receiving mixture of picture-phone terminal data is analyzed with constant service times, synchronous transmission, and single-server interruptions through first-order…