Using constraints with cluster analysis limits the possible number of clusters. This paper deals with clustering problems where grouping is constrained by a symmetric and reflexive relation. Two approaches, along with illustrations, are presented. (Author/JKS)

A general class of nonhierarchical clustering models and associated algorithms for fitting them are presented. These models generalize the Shepard-Arabie Additive clusters model. Two applications are given and extensions to three-way models, nonmetric analyses, and other model specifications are provided. (Author/JKS)

The Rasch model and other latent trait models encounter some difficulty when faced with an appreciable amount of missing data or omitting behavior. The present note assumes that some reasonable missing data model has been formulated which does not involve the parameters associated with the latent ability of interest. A maximum likelihood function…

A strategy for the pairwise assessment which may be used to evaluate the nature of both "prerequisite" and "transference" relations existing among a set of traits is presented. Both confirmatory and exploratory strategies are presented. An example of how the strategy would be used is presented in the exploratory context.…

Decomposable models, which allow for the interdependence of structure among observable variables, are described. Each model is fully characterized by a set of conditional interdependence restrictions and can be visualized with an undirected as well as a special type of directed graph. (Author/JKS)

The Goodman technique of log linear analysis is ideal for family research, because it is designed for categorical (non-quantitative) variables. Variables are dichotomized (for example, married/divorced, childless/with children) or otherwise categorized (for example, level of permissiveness, life cycle stage). Contingency tables are then…

THE STUDIES EMBODIED IN THIS REPORT PROPOSE SOME STATISTICAL METHODS OF ORDERING AND ATTAINING RELEVANCY TO HELP THE EDUCATIONAL RESEARCHER CHOOSE AMONG SUCH VARIABLES AS TESTS AND BEHAVIOR RATINGS. CONSTRUCTION OF A MODEL FOR THE ANALYSIS OF CONTINGENCY TABLES, DETERMINATION OF THE MOST APPROPRIATE ORDERING PRINCIPLE IN STEP-DOWN ANALYSIS FOR THE…

A WORKING MODEL CAPABLE OF RANKING INDIVIDUALS IN A RANDOM SAMPLE FROM A MULTIVARIATE POPULATION BY SOME CRITERION OF INTEREST WAS DEVELOPED. THE MULTIPLE CORRELATION COEFFICIENT OF RANKS WITH MEASURED VARIATES AS A STATISTIC IN TESTING WHETHER RANKS ARE ASSOCIATED WITH MEASUREMENTS WAS EMPLOYED AND DUBBED "QUASI-RANK MULTIPLE CORRELATION…

This study involved an investigation of the use of Pearson r, tetrachoric r, phi, phi/phi maximum, and Kendall Tau-B coefficients as measures of association for the incomplete principal components analysis of simulated Likert scale attitudinal data, based on a known factor pattern and possessing different types of severe departures from normality.…

A statistical test is described which determines homogeneity of effect size of an experiment series. An overall fit statistic is partitioned into between-class fit statistic and within-class fit statistic. These statistics permit assessment of differences between effect sizes for different classes and homogeneity of effect size within classes.…

The general goal of this paper is to help researchers conduct appropriately designed goodness of fit studies for item response model applications. The specific purposes are to describe: (1) an up-to-date set of promising and useful methods for addressing a variety of goodness of fit questions; and (2) current research studies to advance this set…