Underpowered studies persist in the psychological literature. This article examines reasons for their persistence and the effects on efforts to create a cumulative science. The "curse of multiplicities" plays a central role in the presentation. Most psychologists realize that testing multiple hypotheses in a single study affects the Type I error…

Based on seminal work by Lord and Hambleton, Swaminathan, and Rogers, this article is an analytical, graphical, and conceptual reminder that item response theory (IRT) parameter invariance only holds for perfect model fit in multiple populations or across multiple conditions and is thus an ideal state. In practice, one attempts to quantify the…

This manuscript introduces a new Bayesian finite mixture methodology for the joint clustering of row and column stimuli/objects associated with two-mode asymmetric proximity, dominance, or profile data. That is, common clusters are derived which partition both the row and column stimuli/objects simultaneously into the same derived set of clusters.…

The Kentucky Education Excellence Scholarship (KEES) is a merit-based scholarship program intended to increase college access, long-term academic commitment, and retention of top students within the state. KEES uses a heavily graduated award structure and both high school grade point average and standardized test scores to establish award amounts.…

In this study, we examine the role of academic preparation in the transition from community colleges to four-year institutions. We address two specific questions: To what extent do academically unprepared students transfer to four-year institutions? And, can positive experiences in community colleges diminish the role of inadequate academic…

We illustrate a class of multidimensional item response theory models in which the items are allowed to have different discriminating power and the latent traits are represented through a vector having a discrete distribution. We also show how the hypothesis of unidimensionality may be tested against a specific bidimensional alternative by using a…

Describes the strengths and weaknesses of a new type of multivariate technique, covariance structure analysis (LISREL). Provides a detailed example which shows how the use of covariance structure analysis can improve research sophistication and theory development in counseling psychology. (Author/ABB)

A simplified example of a technique, conceived by Yates and later developed by Goodman and Haberman, for the determination of appropriate log-models in the measurement of qualitative data in higher education is presented. (Author/MLW)

Following the assumptions of ecological socialization research, adequate analysis of socialization conditions must take into account the multilevel and multivariate structure of social factors that impact on human development. This statement implies that complex models of family configurations or of socialization factors are needed to explain the…

There are two main theories with respect to the development of spelling ability: the stage model and the model of overlapping waves. In this paper exploratory model based clustering will be used to analyze the responses of more than 3500 pupils to subsets of 245 items. To evaluate the two theories, the resulting clusters will be ordered along a…

Considerable attention has been given to the efficacy of team-learning pedagogy, yet the methodology remains underused among educators in institutions of higher education. We suggest that the perception of success is antecedent to greater acceptance and use of this teaching style. Educators and students alike must experience the value creation…

Methodological implications of a person-oriented, holistic-interactionistic perspective in research on individual development are outlined, desirable properties of a mathematical model of a phenomenon are discussed, and selected methods for carrying out person-oriented research are briefly overviewed. These methods are: (1) the classificatory…

Three analyses of /-t,d/ deletion are undertaken to investigate whether convergence with the matrix regional dialect has taken place in Los Angeles Chicano English. Two superficial analyses mistakenly find convergence. A third emic multivariate analysis finds no phonological convergence. (33 references) (Author/CK)

Describes a study that recorded the type and severity of body movements of 79 boys with ADHD (attention deficit hyperactivity disorder) and 67 non-ADHD boys while playing a computer video game. Results of multivariate analysis of variance showed no statistically significant differences in body movements between ADHD and non-ADHD boys. (Author/LRW)

Item bias is a major threat to measurement validity. Methods for detecting differential item functioning (DIF) are now commonly used to identify potentially biased items. DIF detection methods for dichotomous items are well developed, but those for ordinal items are less well developed. In this article, the authors compare four methods for…