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)

Arguments by J. Levin (1988) challenging the convergence properties of the Harman and Jones (1966) method of Minres factor analysis are shown to be invalid. Claims about the invalidity of a rank-one version of the Harman and Jones method are also refuted. (TJH)

A nonspatial operationalization of the Krumhansl distance-density model of similarity is presented. The conceptual model and empirical evidence are reviewed. A nonspatial, tree-fitting methodology is described, which is sufficiently flexible to fit several competing hypotheses of similarity formation. Extensions to spatial models, three-way…

Presents a model for resource allocation of state-prevention funds based on the relative need for prevention services measured in terms of composite risk-factor index scores computed for each county. Suggests that funding be based on the resource-allocation algorithms rather than the suggested amount of funding computed for each county.…

Presents a domain-specific thesaurus for linguistic support of an information broker that employs an adaptive semantic-distance function based on pathfinder networks and algorithms for automated population by nominal compound interpretation and relational inheritance. Mathematical structure of thesauri and issues for further research are also…