John T. Behrens

Principles and procedures of exploratory data analysis.

Exploratory data analysis (EDA) is a well-established statistical tradition that provides conceptual and computational tools for discovering patterns to foster hypothesis development and refinement. These tools and attitudes complement the use of significance and hypothesis tests used in confirmatory data analysis (CDA). Although EDA complements rather than replaces CDA, use of CDA without EDA is seldom warranted. Even when well-specified theories are held, EDA helps one interpret the results of CDA and may reveal unexpected or misleading patterns in the data. This article introduces the central heuristics and computational tools of EDA and contrasts it with CDA and exploratory statistics in general. EDA techniques are illustrated using previously published psychological data. Changes in statistical training and practice are recommended to incorporate these tools.

Does the White Racial Identity Attitude Scale Measure Racial Identity

Competing interpretations of the structure of the White Racial Identity Attitude Scale (WRIAS; J. E. Helms & R. T. Carter, 1990) were assessed in 2 investigations. First, a meta-analysis of scale intercorrelations and internal reliability estimates indicated that, after correction for measurement error, intercorrelations between some scales were equal to unity, suggesting that the structure of the WRIAS is less complex than the theory of White racial identity it is assumed to measure. Second, confirmatory factor analysis of 2 data sets likewise revealed that scale structures found in the data are more parsimonious than those suggested by theory. Although it remains unclear which construct or constructs are actually measured by the instrument, interpretations of the WRIAS as composed of 5 meaningful dimensions are unsupported.

Depression And Cognitive Self-Statements Of Learning Disabled And Seriously Emotionally Disturbed Adolescents

Prevalence and severity of depression and related negative cognitive self-statements were assessed in a sample of 465 junior and senior high school learning disabled (LD) and seriously emotionally disturbed (SED) adolescents receiving special education services in public school resource room programs. Twenty-one percent of the adolescents sampled experienced severe depressive symptomatology. Some senior high females exhibited a more negative cognitive style than their male peers, although no differences were found at the junior high level. There were no differences in severity of depressive symptomatology and related dysfunctional cognitive self-statements between LD and SED students. Results indicate that depression is a prevalent condition among many LD and SED adolescents, a finding that warrants increased attention among special educators. Implications for expanding school-based identification and intervention procedures are discussed.

APPLICATIONS OF MULTIVARIATE VISUALIZATION TO BEHAVIORAL SCIENCES

The complexity of psychological science often requires the collection and analysis of multidimensional data. Such data bring about a corresponding cognitive load that has led scientists to develop techniques of scientific visualization to ease the burden. This paper provides an introduction to scientific visualization techniques, a framework for understanding those techniques, and an assessment of the suitability of this approach for psychology. The framework employed builds on the notion of balancingnoise andsmooth in statistical analysis.

Judgment Errors in Elementary Box-Plot Displays

Using elementary box-plots as stimuli, in this empirical investigation it was established that box-length and whisker- length judgments are systematically affected by the relation between box and whisker length. These results are consistent with theory and findings of psychological investigations of the Baldwin illusion (Girgus and Coren (1982); Jordan and Schiano, (1986); Pressey and Smith (1986)).

The effects of performance expectation and question difficulty on text study time, response certitude, and correct responding

On the basis of a premise that persons modify studying behavior in order to maintain response certitude at acceptable levels, performance expectations and question difficulty were varied factorially in two studies, and their effects on study time, correct responding, and response certitude were evaluated. The manipulations did not affect study time, but correct responding was in the anticipated direction in both studies, significantly so in Experiment 2. For response certitude, an expected interaction of performance expectation × question difficulty × trial was in the anticipated direction in both studies, significantly so in Experiment 1.