The relationship between saturated path-analysis models and their fit to data is revisited. It is demonstrated that a saturated model need not fit perfectly or even well a given data set when fit to the raw data is examined, a criterion currently frequently overlooked by researchers utilizing path analysis modeling techniques. The potential of…

A correlation structure modeling method for comparison of mediated effects is outlined. The procedure permits point and interval estimation of differences in mediator effects, and is useful with models postulating 1 or more predictor, intervening, or response variables that may also be latent constructs. The approach allows scale-free evaluation…

The usefulness of structural equation modeling methodology for studying change is explored, considering individual and group change model classes. The relationship between the constant rate of change and simplex models as representatives of either class is examined, and both models are shown to be special cases of comprehensive latent curve…

Studied the population discrepancy of coefficient alpha from the composite reliability coefficient for fixed congeneric measures with correlated errors and expressed it in terms of parameters of the measures. Recommends structural equation modeling for identifying cases in which the discrepancy can be large. (SLD)

Discusses the difference in noncentrality parameters of nested structural equation models and their utility in evaluating statistical power associated with the pertinent restriction test. Asymptotic confidence intervals for that difference are presented. These intervals represent a useful adjunct to goodness-of-fit indexes in assessing constraints…

It is shown that, for equivalent structural equation models that have been extended to multigroup models, imposing cross-group equality constraints on no parameters, all parameters, or any number of parameters for which the models are identical preserves the model equivalence property. Results are illustrated with two-group cognitive intervention…

Structural equation modeling is used in the simultaneous study of individual and group latent change patterns on several longitudinally assessed variables. The approach, which is based on a special case of the comprehensive latent curve analysis of W. Meredith and J. Tisak (1990), is illustrated with a two-group study. (SLD)

A general structural modeling approach to correlates and predictors of change in multiwave design is discussed. It allows estimation of theoretically and empirically relevant interrelationship indexes between growth and decline in longitudinally assessed psychological constructs and additional variables. Data from a study of aged adults illustrate…

Examines the relationship between Cronbach's coefficient alpha and the reliability of a composite of a prespecified set of interrelated nonhomogeneous components through simulation. Shows that alpha can over- or underestimate scale reliability at the population level. Illustrates the bias in terms of structural parameters. (SLD)

A general structural equation model for measuring residualized true change and studying patterns of true growth or decline is described. This approach allows consistent and efficient estimation of the degree of interrelationship between residualized change in a repeatedly assessed psychological construct and other variables. (SLD)

The ability of 248 older adults to improve their performance on fluid intelligence tests, with or without tutor-guided instruction in cognitive skills, was studied using multidimensional longitudinal structural equation models. Results suggest considerable plasticity in adult intellectual function and the capacity to improve performance. (SLD)