Outliers are typically regarded as data anomalies that should be discarded. However, dynamic or "innovative" outliers can be appropriately utilized to capture unusual but substantively meaningful shifts in a system's dynamics. We extend De Jong and Penzer's 1998 approach for representing outliers in single-subject state-space models to a…

In their seminal paper, Edwards and Parry (1993) presented the polynomial regression as a better alternative to applying difference score in the study of congruence. Although this method is increasingly applied in congruence research, its complexity relative to other methods for assessing congruence (e.g., difference score methods) was one of the…

This investigation analyzed the diagnostic utility of subtest scores in differentiating between underachieving children and children who were adequately achieving. The use of derived classification equations from group statistics in individual diagnosis led to dramatic levels of misclassification among underachieving students. (Author/CTM)

Three estimates of the probabilities of correct classification in predictive discriminant analysis were computed using mathematical formulas, resubstitution, and external analyses: (1) optimal hit rate; (2) actual hit rate; and (3) expected actual hit rate. Methods were compared using Monte Carlo sampling from two data sets. (Author/GDC)

The impact of misspecification on the estimation, testing, and improvement of structural equation models was assessed via a population study in which a prototypical latent variable model was misspecified. Results provide insights into the maximum likelihood estimator versus a limited two-stage least squares estimator in LISREL. (TJH)

The study tests the appropriateness of multiplicative versus additive expectancy-valency models for grouping motivational force decisions of 82 undergraduate students. Arguments are offered favoring a non-nested regression models analysis over a traditional hierarchical analysis of nested regression models. Discriminant analysis indicated one of…

A procedure is suggested for test development and construct validation based on a theory about the criterion performance. The method is illustrated by describing a study concerned with the selection of medical school students, where the criterion is a measure of clinical problem-solving ability. (Author/LMO)