A model of interference and forgetting based on the search of associative memory (SAM) theory is presented. The SAM theory describes retrieval processes in long-term memory. A model of contextual fluctuation processes is incorporated to provide a time-dependent variable to handle time-based interference phenomena. (SLD)

Two-group classification is discussed when a unidimensional latent trait "theta" is appropriate for explaining data. If data have a monotone likelihood ratio, then optimal allocation rules can be based on its magnitude when allocation must be made to one of the two groups related to the unidimensional latent trait. (SLD)

The effects of several specification search strategies used with Covariance Structure Modeling to obtain more parsimonious models are examined. The initial models vary in their degree of "correctness." Restricting modifications to those justified by prior theoretical knowledge improves the success of a specification search. (TJH)

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)

Presents the list-structure data model for dealing with sets of objects, which has ordering as its fundamental principle. An extended notion of patterns and several operators of the algebra are presented. Design issues that influenced the development of the language are described. (Contains 30 references.) (KRN)

Point-estimate and confidence-interval procedures are proposed for the (1) combined Mann-Whitney U test; (2) combined two-sample normal-scores test; (3) combined matched-pair Wilcoxon signed-ranks test; and (4) combined matched-pair normal-scores test. The four techniques are illustrated with hypothetical examples and are considered either…

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)

Introduces a new measure of bargaining toughness based on dynamical information that can easily be used in integrative bargaining scenarios. Develops a mathematical measure of bargaining toughness that takes into account not only how much the bargainer has conceded but how fast he or she has done so. (RS)

Introduces Rene Thom's catastrophe theory, which is based upon complex theorems in multidimensional geometry. Catastrophe theory analysis begins by identifying the occurrence of major discontinuities, or catastrophes, in a system such as civil service exams, resulting in catastrophic change. (KS)

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)

Presents a mathematical model for projecting class cohort sizes for districts and schools via demographic data. The model allows entry of estimates for local preschool data to predict first-grade entrants, which are progressed through the school system. Average retention rates, school apportionments and national demographic projections can be…

This article offers comments and clarifications of Egghe's paper, which dealt with information production processes (IPP) and the Gini index. Topics addressed include the length of the Lorenz curve as a concentration measure, the discrete duality operator, and a Bradford-Leimkuhler distribution. (10 references) (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)

An asymmetric version of J. Cohen's kappa statistic is presented as an appropriate measure for the agreement between two observers classifying items into nominal categories, when one observer represents the "standard." A numerical example with three categories is provided. (SLD)