Describes the development of a structural model of document retrieval based on lexical-semantic relationships between index terms. An algorithm that uses tree-to-tree distance to measure structural closeness between a document and a query statement is explained, and the proposed model is compared to a vector retrieval model. (18 references) (LRW)

Two zero-one linear programing models for constructing tests using classical item and test parameters are given. These models are useful, for instance, when classical test theory must serve as an interface between an item response theory-based item banking system and a test constructor unfamiliar with the underlying theory. (TJH)

Reviews models currently used to describe the retrieval process and questions whether extensions of traditional approaches can provide mechanisms for expert retrieval systems. An alternative view in which retrieval is based on concept space is presented. A logic framework is used to define a semantic model for using knowledge contained in concept…

The frequencies of "m" independent "p-way" contingency tables are analyzed by a model that assumes that the ordinal category data in each of "m" groups are generated from a latent continuous multivariate normal distribution. The model permits analysis of several groups of individuals simultaneously. (TJH)

A maximin model for test design based on item response theory is proposed. Only the relative shape of target test information function is specified. It serves as a constraint subject to which a linear programing algorithm maximizes the test information. The model is illustrated, and alternative models are discussed. (TJH)

A longitudinal factor analysis model that is entirely exploratory is proposed for use with multiple populations. Factorial collapse, period/practice effects, and an invariant and/or stationary factor pattern are allowed. The model is formulated stochastically and implemented via a stage-wise EM algorithm. (TJH)

The DEDICOM (decomposition into directional components) model provides a framework for analyzing square but asymmetric matrices of directional relationships among "n" objects or persons in terms of a small number of components. One version of DEDICOM ignores the diagonal entries of the matrices. A straightforward computational solution…

Examines parallel computer architecture and the use of parallel processors for text. Topics discussed include parallel algorithms; performance evaluation; parallel information processing; parallel access methods for text; parallel and distributed information retrieval systems; parallel hardware for text; and network models for information…

Discussion of the failure of individual keywords to identify conceptual content of documents in retrieval systems highlights Metric Similarity Modeling, a method for creating vector space representation of documents based on modeling target interdocument similarity values. Semantic relatedness, latent semantic indexing, an indexing and retrieval…

Describes a new data compression technique that utilizes the common morphological structure of languages. Topics include classification of languages and their morphological structure; structured text compression; the algorithm and an example using Turkish; theoretical implications; and implementation. (LRW)

It is proposed that attributes of automatization depend on the strength of a processing pathway, and that strength increases with training. With the Stroop effect as an example, automatic processes are shown through simulation to be continuous and to emerge gradually with practice. (SLD)

Examines the retrieval effectiveness of five hierarchical clustering methods (single link, complete link, group average, Ward's method, and weighted average) as a function of indexing exhaustivity with four test collections. Evaluations of retrieval effectiveness are based on three measures of optimal retrieval performance. (Author/LRW)

A procedure is described for minimizing a class of matrix trace functions, which is a refinement of an earlier procedure for minimizing the class of matrix trace functions using majorization. Several trial analyses demonstrate that the revised procedure is more efficient than the earlier majorization-based procedure. (SLD)

A globally optimal solution is presented for a class of functions composed of a linear regression function and a penalty function for the sums of squared regression weights. A completing-the-squares approach is used, rather than calculus, because it yields global minimality easily in two of three cases examined. (SLD)

Discusses issues relevant to end users when choosing digital video technology. Topics addressed include Indeo video, an algorithm for the capture and compression of digital video; cross-platform capability; products from Intel, including possible future developments; and international standards for video. (LRW)