Accuracy was compared for three methods of implementing parallel analysis with mean eigenvalues (regression, interpolation, and computation with three samples of random data). The accuracy of parallel analysis with 95th percentile eigenvalues (through regression and interpolation) was also considered. No evidence of differential accuracy emerged…

The Little Jiffy" consists of principal components analysis and varimax rotation of all components with eigenvalues greater than one. (DG)

Effects of different weighting schemes on selecting the optimal number of observations in multivariate-multifacet generalizability designs are studied when cost constraints are imposed. Comparison of four schemes through simulation indicates that all four produce similar optimal values and that reliability should be similar. (SLD)

A useful method is proposed for identifying a variable as inconsistent in factor analysis. The procedure, based on the likelihood principle, is illustrated. Statistical properties such as the effect of misspecified hypotheses, the problem of multiple comparisons, and robustness to violation of distributional assumptions are investigated. (SLD)

Multivariate methods were used to identify between-set factors relating the criterion set of eleven Wechsler Adult Intelligence Scale Revised subtest variables to the predictor set of demographic variables: age, race, sex, education, occupation, geographic region, and urban versus rural residence. Although factor analysis is usually used to…

Using simulated and real data, this study compares the performance of three methodologies for assessing unidimensionality: (1) DIMTEST; (2) the approach of Holland and Rosenbaum; and (3) nonlinear factor analysis. All three models correctly confirm unidimensionality, but they differ in their ability to detect the lack of unidimensionality.…

Two analyses of variance (ANOVA) models for item scores are compared. The first is an items by subject random effect ANOVA. The second is a mixed effects ANOVA with items fixed and subjects random. Comparisons regarding reliability, Cronbach's alpha coefficient, psychometric inference, and inter-item covariance structure are made between the…

A population data set was randomly generated from which a random sample was drawn. This sample was randomly divided into two data sets, one of which was used to generate parameter estimates, which were then used in the second data set for cross-validation purposes. The best variable subset models were compared between the two data sets on the…

Four methods for determining the dimensionality of a set of test items were compared: (1) linear factor analysis; (2) residual analysis; (3) nonlinear factor analysis; and (4) Bejar's method. Five artificial test data sets (for 40 items and 1500 examinees) were generated, consistent with the three-parameter logistic model and the assumption of…

Despite advances in common factor analysis, a review of 89 studies published in four selected journals between 1963 and 1976 indicated that behavioral scientists preferred principal components analysis, followed by varimax or orthogonal rotation. Resultant row sums of squares of factor matrices from principal component analyses of real data sets…

A procedure for assessing content-area and total-test dimensionality which uses response function discrepancies (RFD) was studied. Three different versions of the RFD procedure were compared to Bejar's principal axis content-area procedure and Indow and Samejima's exploratory factor analytic technique. The procedures were compared in terms of the…

The TESTFACT computer program and full-information factor analysis of test items were used in a computer simulation conducted to correct for the guessing effect. Full-information factor analysis also corrects for omitted items. The present version of TESTFACT handles up to five factors and 150 items. A preliminary smoothing of the tetrachoric…

Project ABRAZO, a Spanish bilingual project in 4 urban schools having over 50% Mexican American composition, operates with the objective of conducting research related to the self-concept of Mexican American students. In connection with ABRAZO, this paper focuses on describing the ABRAZO schools by reporting on the administration of Halpin and…

The report is one of four that describes the 1977 phase of an ongoing series of studies by the association. The purpose of the studies is to examine the interrelationships among variables and institutions based on the descriptive measures contained in the Institutional Profile System, which contains a vast array of data on medical schools…

Two rural Louisiana communities were selected to evaluate the effectiveness of certain types of communication in preventing man-caused forest fires. The communities were selected on the basis of differences in fire occurrence rates and other factors related to conservation. Questionnaires and personal interviews were utilized to determine views of…