Some properties of the correlation matrix of dichotomous guttman items

Both the elements and the eigenvalues of the Pearson correlation matrix of dichotomous Guttman-scalable items can be expressed as simple functions of the number of items if the score distribution is uniform and there is an equal number of items at each difficulty level. Even when these special conditions do not hold, the correlations can often be expressed in a simple form by assuming a particular score distribution.The author thanks Neil Dorans, Bob Mislevy, Ledyard R Tucker, and Howard Wainer for their comments.     

Parent-perceived child behavior problems: Comparison of normative and clinical factors of the Adelaide-Conners Parent Rating Scale

The Adelaide-Conners Parent Rating Scale (APRS), an instrument developed by studying a large, representative group of schoolchildren, was used with a group of psychiatry attenders. Multimethod factor analysis found satisfactory agreement between the factor structures of the clinical and the normative groups. The patterns of scores on the 12 APRS scales were also compared. Two higher-order factors (Conflict with the Environment and Conflict within the Self) were identified in the clinical sample as previously found in the normative group. Comparison of the factor solutions with previous empirical efforts to identify parent-perceived patterns of child behavior disorder showed that the APRS compares well with other instruments and supports the strategy of proceeding from the study of normative populations to the study of clinically defined groups.This work was supported in part by a grant from the Department of Health, Canberra.     

BENEFITS AND COSTS OF SUPPORTED EMPLOYMENT: AN ANALYSIS OF THE ILLINOIS SUPPORTED EMPLOYMENT PROJECT

This investigation presents a cost-benefit analysis completed for one of 27 states implementing supported employment as a result of federal funding. Based upon the benefits and costs detailed, society realized a $0.75 return for every $1.00 invested in supported employment in Illinois. Supported employees realized a 37% increase in their earnings over a comparable period. The results of this study are discussed and recommendations are made for similar analyses across states.     

An alternating least squares algorithm for fitting the two- and three-way dedicom model and the idioscal model

The DEDICOM model is a model for representing asymmetric relations among a set of objects by means of a set of coordinates for the objects on a limited number of dimensions. The present paper offers an alternating least squares algorithm for fitting the DEDICOM model. The model can be generalized to represent any number of sets of relations among the same set of objects. An algorithm for fitting this three-way DEDICOM model is provided as well. Based on the algorithm for the three-way DEDICOM model an algorithm is developed for fitting the IDIOSCAL model in the least squares sense.The author is obliged to Jos ten Berge and Richard Harshman.     

Pseudo maximum likelihood estimation and a test for misspecification in mean and covariance structure models

Using the theory of pseudo maximum likelihood estimation the asymptotic covariance matrix of maximum likelihood estimates for mean and covariance structure models is given for the case where the variables are not multivariate normal. This asymptotic covariance matrix is consistently estimated without the computation of the empirical fourth order moment matrix. Using quasi-maximum likelihood theory a Hausman misspecification test is developed. This test is sensitive to misspecification caused by errors that are correlated with the independent variables. This misspecification cannot be detected by the test statistics currently used in covariance structure analysis.For helpful comments on a previous draft of the paper we are indebted to Kenneth A. Bollen, Ulrich L. Küsters, Michael E. Sobel and the anonymous reviewers of Psychometrika. For partial research support, the first author wishes to thank the Department of Sociology at the University of Arizona, where he was a visiting professor during the fall semester 1987.     

Fitting the off-diagonal dedicom model in the least-squares sense by a generalization of the harman and jones minres procedure of factor analysis

Harshman's DEDICOM model providesa framework for analyzing square but asymmetric materices of directional relationships amongn objects or persons in terms of a small number of components. One version of DEDICOM ignores the diagonal entries of the matrices. A straight-forward computational solution for this model is offered in the present paper. The solution can be interpreted as a generalized Minres procedure suitable for handing asymmetric matrices.     

An investigation of the normative and factor analytic composition of six questionnaires used for subject selection

Six self-report instruments which have been widely used for subject screening were administered to large samples of males and female college students. Normative information and bivariate correlations between scales were derived. Principal components analysis was applied to the individual scales to determine substructures. Finally, factor scores from the scales were examined in terms of second-order factors from an additional principal components analysis. The results are discussed in terms of comparisons with the results of previously published reports and implications for the discriminant validity of the scales and factor scores. The use of factor scores for more homogeneous subject selection is suggested.We wish to thank Arnold Holzman, Cynthia Volinsky, Ellen Tuckner, and Patricia Tolchin for their assistance in administering the questionnaires. Appreciation is also extended to Paul Malloy for his aid and suggestions concerning data analysis and to an anonymous reviewer for insightful comments which improved the quality of the final report. This study was conducted while the first author was at the State University of New York at Binghamton.     

Factor analysis by instrumental variables methods

Three alternative estimation procedures for factor analysis based on the instrumental variables method are presented. These procedures are justified by the method of least squares. Formulas for asymptotic standard errors of factor loadings are derived. The procedures are empirically compared to the method of maximum likelihood. The conclusion, based on the data used in this study, is that two of the procedures seem to work well.     

The technical drift of applied behavior analysis

Four dimensions (applied, analytic, general, conceptual) were selected from Baer, Wolf, and Risley's (1968) seminal article on the nature of applied behavior analysis and were monitored throughout the first 10 volumes of the Journal of Applied Behavior Analysis. Each of the experimental articles in Volumes 1 through 6 and the first half of Volumes 7 through 10 was rated on each of these dimensions. The trends showed that applied behavior analysis is becoming a more purely technical effort, with less interest in conceptual questions. We are using simpler experimental designs and are conducting fewer analogue studies. Although concern for maintenance is increasing, other forms of generality are being measured or analyzed less often. These trends are discussed in terms of a technical drift in applied behavior analysis.     

Statistics as psychometrics

In this paper, modern statistics is considered as a branch of psychometrics and the question of how the central problems of statistics can be resolved using psychometric methods is investigated. Theories and methods developed in the fields of test theory, scaling, and factor analysis are related to the principle problems of modern statistical theory and method. Topics surveyed include assessment of probabilities, assessment of utilities, assessment of exchangeability, preposterior analysis, adversary analysis, multiple comparisons, the selection of predictor variables, and full-rank ANOVA. Reference is made to some literature from the field of cognitive psychology to indicate some of the difficulties encountered in probability and utility assessment. Some methods for resolving these difficulties using the Computer-Assisted Data Analysis (CADA) Monitor are described, as is some recent experimental work on utility assessment.1980 Psychometric Society presidential address.I am indebted to Paul Slovic and David Libby for valuable consultation on the issues discussed in this paper and to Nancy Turner and Laura Novick for assistance in preparation.Research reported herein was supported under contract number N00014-77-C-0428 from the Office of Naval Research to The University of Iowa, Melvin R. Novick, principal investigator. Opinions expressed herein reflect those of the author and not those of sponsoring agencies.