The effect of stratified sampling of items on the estimation of test score distribution parameters by multiple matrix sampling was studied. Item difficulty and/or interitem correlations were the bases of stratification. Various item iniverses were created by computer simulation and sampled according to several plans. The results indicate that…

A general purpose computer program for the calculation of a matrix of tetrachoric correlations is described. This program was developed for use in adaptive (and other) testing research for examining the unidimensionality assumption in latent trait theory, in conjunction with available factor analysis programs. Several other potential applications,…

The purpose of this paper is to demonstrate the use of the general linear model (GLM) in problems with repeated measures on a dependent variable. Such problems include pretest-posttest designs, multitrial designs, and groups by trials designs. For each of these designs, a GLM analysis is demonstrated wherein full models are formed and restrictions…

APL (A Programing Language), a computer language used thus far largely for mathematical and scientific applications, can be used to tabulate a survey. Since this computer application can be appreciated by social scientists as well as mathematicians, it serves as an invaluable pedagogical tool for presenting APL to nonscientific users. An…

In some correlational studies it is not reasonable to assume that bivariate observations are uncorrelated. An example would be a configural analysis in which two individuals are correlated across several variables (e.g., Q-technique). The present study was a Monte Carlo investigation of the robustness of techniques used in judging the magnitude of…

Unit 23 in the SMSG secondary school mathematics series is a student text covering the following topics in matrix algebra: matrix operations, the algebra of 2 X 2 matrices, matrices and linear systems, representation of column matrices as geometric vectors, and transformations of the plane. Listed in the appendix are four research exercises in…

Several procedures proposed in the literature for the analysis of growth curves are reviewed. Particular attention is given to the current issues in this area to guide practitioners in the selection of the most appropriate methodology. (Author)

When the variance assumptions of a repeated measures ANOVA are not met, the F distribution of the mean square ratio should be adjusted by the sample estimate of the Box correction factor. An alternative is proposed which is shown by Monte Carlo methods to be less biased for a moderately large factor. (RC)

Cancer centers have evolved several types of administrative structures, the most successful using some modification of a matrix system with delegation of significant administrative authority to the center. The author suggests implications for other multidisciplinary centers which find themselves in conflict with traditional discipline…

Students were presented with the problem of finding all magic squares of order three. (SD)

The t ratio used in testing the difference between two independent regression coefficients is generalized to the multivariate case of testing the difference between two vectors of regression coefficients. This is particularly useful in determining which of two variables best predicts a number of criterion variables. (Author/JKS)

A method for estimating variance-covariance matrices with incomplete data for use in discriminant function analysis is presented. An example of its use in college algebra course placement is also presented. (JKS)

The problem of comparing two sociometric matrices, as originally discussed by Katz and Powell in the early 1950's, is reconsidered and generalized using a different inference model. In particular, the proposed indices of conformity are justified by a regression argument similar to the one used by Somers. ( Author/JKS)

Chio's method of evaluating determinants by successive reduction of size is explained. (MN)

Scores were obtained on 31 item-clusters from the California Psychological Inventory for 490 identical and 317 same-sex fraternal twin pairs from the National Merit twin sample. Ordinary and cross-pair correlations were calculated and used to derive three matrices hypothesized to reflect the influence of genes, shared environment, and unshared…