Draws attention to an existing methodology for handling decision-making in a typical planning situation of interrelated alternatives and data deficiency, and describes several important extensions that have recently been made to it. (Oriel Press Limited, 32 Ridley Place, Newcastle upon Tyne, NE1 8LH, Great Britain, $7.00 yearly.) (Author)

Illustrated is the power of multidimensional scaling in reducing a complex set of proximity measures to a simple geometric picture that shows the relationship among data objects. Methods are discussed for determining the number of dimensions needed to represent a set. (Author/DEP)

Suggestions are provided for activities involving the construction of mathematical models to solve "real-life" problems. (SD)

Arguing that the teaching of stochastic processes should reflect the experience and reality of the student, the author urges concentration on fundamental ideas. The development of intuition should be encouraged, and to this end continuity in teaching and a spiralled curriculum are important. (SD)

Presents a method of solving decision problems in conditions of incomplete knowledge of the probabilities of the states of nature. It uses all available information in order to delimit the region of ignorance as closely as possible. (Author)

During the past several decades, a new class of measurement theory, called latent trait (or item response) theory, has become popular. Supporters contend that results obtained through the use of this theory prove vastly superior to classical measurement statistics. This paper investigates the use of the Rasch model, one of the more popular latent…

The problem of obtaining designs that result in the most precise parameter estimates is encountered in at least two situations where item response theory (IRT) models are used. In so-called two-stage testing procedures, certain designs that match difficulty levels of the test items with the ability of the examinees may be located. Such designs…

An overview of the state of the art in psychological research is presented, with an emphasis on the attention given to effect sizes. The acceptance of small effect sizes for biomedical research is contrasted with the rejection of similar effect sizes for psychological research. The Binomial Effect Size Display is used to depict the practical…

This LISREL study examines the robustness of the maximum likelihood estimates under varying degrees of measurement model misspecification. A true model containing five latent variables (two endogenous and three exogenous) and two indicator variables per latent variable was used. Measurement model misspecification considered included errors of…

In the process of developing a conditionally-dependent item response theory (IRT) model, the problem arose of modeling an underlying multivariate normal (MVN) response process with general correlation among the items. Without the assumption of conditional independence, for which the underlying MVN cdf takes on comparatively simple forms and can be…

The purposes of the present investigation were to illustrate the applicability of categorization methodology for several empirical situations and to draw implications regarding the use of such methodology in examining categorical data. In using three tasks--two designed to measure cognitive dimensions (e.g., categorizing countries and categorizing…