I-states-as-objects-analysis (ISOA) is a person-oriented methodology for studying short-term developmental stability and change in patterns of variable values. ISOA is based on longitudinal data with the same set of variables measured at all measurement occasions. A key concept is the "i-state," defined as a person's pattern of variable…

Computing the mean and covariance matrix of some multivariate distributions, in particular, multivariate normal distribution and Wishart distribution are considered in this article. It involves a matrix transformation of the normal random vector into a random vector whose components are independent normal random variables, and then integrating…

This paper discusses the use of interactive graphics to teach multivariate data analysis to Psychology students. Three techniques are explored through separate activities: parallel coordinates/boxplots; principal components/exploratory factor analysis; and cluster analysis. With interactive graphics, students may perform important parts of the…

Many black students, female students, and students of low socioeconomic status do not achieve up to their potential in mathematics. A model to explain group differences in performance is presented. Relevant research results are included, along with suggestions for future research to test the model. (PK)

The ability of the microcomputer to compile voluminous and detailed measures of students' learning activities automatically has seemingly outpaced the ability of commonly-used data analysis methods to make effective utilization of this wealth of potentially useful information. This study explores the use of computer-based quantitative methods,…