Werner W. Wittmann

WORKING-MEMORY CAPACITY EXPLAINS REASONING ABILITY - AND A LITTLE BIT MORE

A 1,3,5-trialkoxy benzene having 1-2 carbon atoms in each of the alkoxy-groups is prepared at high overall yields, with minimal formation of hazardous or polluting by-products, by reacting 1,3,5-tribromo benzene with an alkalimetal alcoholate having 1-3 carbon atoms in the molecule in the presence of a copper salt, e.g. cuprous iodide or cupric chloride, and an aprotic solvent such as e.g. dimethylformamide. The product is readily recovered from the reaction mixture in an overall yield as high as 90%.

Working memory capacity — facets of a cognitive ability construct

Abstract Working memory capacity is differentiated theoretically along two dimensions: contents and functions. The resulting 3×3 matrix was operationalized by 23 tasks sampled from the literature. Data for these tasks from 128 participants were analyzed by exploratory and confirmatory factor analysis. Regarding the content facet, spatial working memory was clearly distinct from the other two content categories. A distinction between verbal and numerical working memory was not warranted. On the functional dimension the postulated categories of simultaneous storage and transformation and of coordination could not be separated. The third category was clearly separate from the first two functions. This factor could be interpreted to reflect a mixture of variance due to mental speed and to supervisory functions of the central executive.

Simulation Study on Fit Indexes in CFA Based on Data With Slightly Distorted Simple Structure

Fit indexes were compared with respect to a specific type of model misspecification. Simple structure was violated with some secondary loadings that were present in the true models that were not specified in the estimated models. The c2 test, Comparative Fit Index, Goodness-of-Fit Index, Incremental Fit Index, Nonnormed Fit Index, root mean squared error of approximation, standardized root mean square residual, and the c2/df values were investigated. Simulated data sets with 3 sample sizes (250, 500, and 1,000 cases), 4 levels of main loadings (.40,. 50,. 60, and. 80), 2 numbers of factors (4, 8), and 2 types of association matrix (covariance, correlation) were the basis for maximum likelihood estimation of orthogonal and oblique factor models. Some correlations between fit indexes were low. Moreover, small distortions from simple structure did not lead to misfit in the RMSEA and SRMR, but they often led to misfit in the incremental fit indexes. This result may be of interest for research on personality traits, where small violations of simple structure are very common.

Benefits and challenges in practice-oriented psychotherapy research in Germany: The TK and the QS-PSY-BAY projects of quality assurance in outpatient psychotherapy

Abstract Objective: Two patient-focused long-term research projects performed in the German outpatient psychotherapy system are focused on in this article. The TK (Techniker Krankenkasse) project is the first study to evaluate a quality assurance and feedback system with regard to its practical feasibility in German routine care. The other study (“Quality Assurance in Outpatient Psychotherapy in Bavaria”; QS-PSY-BAY) was designed to test a new approach for quality assurance in outpatient psychotherapy using electronic documentation of patient characteristics and outcome parameters. In addition this project provides the opportunity to analyze data on health-related costs for the patients undergoing outpatient psychotherapy. Method: Both projects and their results indicating high effect sizes are briefly described. Results: From the perspectives of the research teams, advisory boards and other stakeholders, the experiences with these projects are discussed focusing on obstacles, challenges, difficulties, and benefits in developing and implementing the studies. The triangle collaboration of therapists, researchers, and health insurance companies/health service institutions turned out to be fruitful in both studies. Conclusions: Despite some controversies between the partners the experiences indicate the importance of practiced-research collaborations to provide relevant information about the delivery of outpatient psychotherapy in the health system.

Feedback and therapist effects in the context of treatment outcome and treatment length

Abstract Objective: This study estimates feedback and therapist effects and tests the predictive value of therapists’ and patient attitudes toward psychometric feedback for treatment outcome and length. Methods: Data of 349 outpatients and 44 therapists in private practices were used. Separate multilevel analyses were conducted to estimate predictors and feedback and therapist effects. Results: Around 5.88% of the variability in treatment outcome and 8.89% in treatment length were attributed to therapists. There was no relationship between the average effectiveness of therapists and the average length of their treatments. Initial impairment, early alliance, number of diagnoses, feedback as well as therapists’ and patients’ attitudes toward feedback were significant predictors of treatment outcome. Treatments tended to be longer for patients with a higher number of approved sessions by the insurance company, with higher levels of interpersonal distress at intake, and for those who developed negatively (negative feedback) over the course of their treatment. Conclusions: Therapist effects on treatment outcome and treatment length in routine care seem to be relevant predictors in the context of feedback studies. Therapists’ attitudes toward and use of feedback as well as patients’ attitudes toward feedback should be further investigated in future research on psychometric feedback.

A critical meta-analysis of Lens Model Studies in human judgment and decision-making

Achieving accurate judgment (‘judgmental achievement’) is of utmost importance in daily life across multiple domains. The lens model and the lens model equation provide useful frameworks for modeling components of judgmental achievement and for creating tools to help decision makers (e.g., physicians, teachers) reach better judgments (e.g., a correct diagnosis, an accurate estimation of intelligence). Previous meta-analyses of judgment and decision-making studies have attempted to evaluate overall judgmental achievement and have provided the basis for evaluating the success of bootstrapping (i.e., replacing judges by linear models that guide decision making). However, previous meta-analyses have failed to appropriately correct for a number of study design artifacts (e.g., measurement error, dichotomization), which may have potentially biased estimations (e.g., of the variability between studies) and led to erroneous interpretations (e.g., with regards to moderator variables). In the current study we therefore conduct the first psychometric meta-analysis of judgmental achievement studies that corrects for a number of study design artifacts. We identified 31 lens model studies (N = 1,151, k = 49) that met our inclusion criteria. We evaluated overall judgmental achievement as well as whether judgmental achievement depended on decision domain (e.g., medicine, education) and/or the level of expertise (expert vs. novice). We also evaluated whether using corrected estimates affected conclusions with regards to the success of bootstrapping with psychometrically-corrected models. Further, we introduce a new psychometric trim-and-fill method to estimate the effect sizes of potentially missing studies correct psychometric meta-analyses for effects of publication bias. Comparison of the results of the psychometric meta-analysis with the results of a traditional meta-analysis (which only corrected for sampling error) indicated that artifact correction leads to a) an increase in values of the lens model components, b) reduced heterogeneity between studies, and c) increases the success of bootstrapping. We argue that psychometric meta-analysis is useful for accurately evaluating human judgment and show the success of bootstrapping.

Adult Age Differences in Inhibitory Processes and their Predictive Validity for Fluid Intelligence

ABSTRACT According to the inhibition-deficit hypothesis age differences in working memory capacity and fluid intelligence have been attributed to a decline in inhibitory efficiency. Conceptualizing inhibition as multifaceted, 88 participants (49 younger and 39 elderly) completed two versions of the negative priming paradigm (identification and localization), and two variants of the directed forgetting paradigm (listwise and itemwise). Two tasks of the Wechsler Intelligence Test with high loadings on general fluid intelligence (Gf) served as validation criteria. Results revealed task-specific and speed-independent inhibitory deficits in the elderly (lower negative priming in both paradigms; more intrusions in the directed forgetting tasks), as well as higher levels of repetition priming. Significant correlations between measures of inhibition and the Wechsler scores were found in both age groups. Results support the view of multiple inhibitory-like capabilities that play a central role in the decline of higher-order cognitive functions in old age.

Effect sizes and F ratios < 1.0. Sense or nonsense?

Abstract. Standard statistics texts indicate that the expected value of the F ratio is 1.0 (more precisely: N/(N-2)) in a completely balanced fixed-effects ANOVA, when the null hypothesis is true. Even though some authors suggest that the null hypothesis is rarely true in practice (e.g., Meehl, 1990), F ratios < 1.0 are reported quite frequently in the literature. However, standard effect size statistics (e.g., Cohens f) often yield positive values when F < 1.0, which appears to create confusion about the meaningfulness of effect size statistics when the null hypothesis may be true. Given the repeated emphasis on reporting effect sizes, it is shown that in the face of F < 1.0 it is misleading to only report sample effect size estimates as often recommended. Causes of F ratios < 1.0 are reviewed, illustrated by a short simulation study. The calculation and interpretation of corrected and uncorrected effect size statistics under these conditions are discussed. Computing adjusted measures of association str...

Assessment of tinnitus-related impairments and disabilities using the German THI-12: Sensitivity and stability of the scale over time

Abstract Objective: To evaluate the reliability, dimensionality, predictive validity, construct validity, and sensitivity to change of the THI-12 total and sub-scales as diagnostic aids to describe and quantify tinnitus-evoked reactions and evaluate treatment efficacy. Design: Explorative analysis of the German tinnitus handicap inventory (THI-12) to assess potential sensitivity to tinnitus therapy in placebo-controlled randomized studies. Correlation analysis, including Cronbachs coefficient α and explorative common factor analysis (EFA), was conducted within and between assessments to demonstrate the construct validity, dimensionality, and factorial structure of the THI-12. Study sample: N = 618 patients suffering from subjective tinnitus who were to be screened to participate in a randomized, placebo-controlled, 16-week, longitudinal study. Results: The THI-12 can reliably diagnose tinnitus-related impairments and disabilities and assess changes over time. The test–retest coefficient for neighboured visits was r > 0.69, the internal consistency of the THI-12 total score was α ≤ 0.79 and α ≤ 0.89 at subsequent visits. Predictability of THI-12 total score and overall variance increased with successive measurements. The three-factorial structure allowed for evaluation of factors that affect aspects of patients’ health-related quality of life. Conclusions: The THI-12, with its three-factorial structure, is a simple, reliable, and valid instrument for the diagnosis and assessment of tinnitus and associated impairment over time. Sumario Objetivo: Evaluar la confiabilidad, dimensionalidad, validez predictiva, validez de la estructura y sensibilidad de cambio del total del THI-12 y las subescalas, como ayuda diagnóstica para describir y cuantificar las reacciones con acúfeno evocado y para evaluar la eficacia del tratamiento. Diseño: Análisis exploratorio del Cuestionario Alemán de Desventaja por Acúfeno (THI-12) para evaluar la sensibilidad potencial de la terapia del acúfeno en estudios al azar, controlados con placebo. Se realizó un análisis de correlación incluyendo el coeficiente a de Cronbach’s y un análisis exploratorio de factor común de análisis (EFA), en y entre evaluaciones, para demostrar la validez de la estructura, la dimensionalidad y la estructura factorial del THI-12. Muestra: N = 618 pacientes con acúfeno subjetivo fueron tamizados para participar en un estudio al azar, controlado por placebo, de 16 semanas y longitudinal. Resultados: El THI-12 puede confiablemente diagnosticar los impedimentos y discapacidades relacionados con el acúfeno y evaluar los cambios en el tiempo. El coeficiente test-retest para visitas cercanas fue de r > 0.69 y la consistencia interna de la puntuación total del THI-12 fue de a ≤ 0.79 y de a ≤ 0.89, en visitas subsecuentes. La previsibilidad de la puntuación total del THI-12 y la variancia global se incrementó con mediciones sucesivas. La estructura factorial triple permitió la evaluación de factores que afectan aspectos que relacionados con la salud y calidad de vida de los pacientes. Conclusiones: El THI-12, con su estructura factorial triple es un instrumento simple, confiable y válido para el diagnóstico y la evaluación del acúfeno y de la discapacidad que con él se asocia, a lo largo del tiempo.

Lessons Learned about Evaluation in the United States and Some Possible Implications for Europe

This paper describes the main lessons learned about evaluation in the United States during the last 25 years and speculates about what some of their implications might be for the growing field of evaluation in Europe. We consider the organizational structure of the field, its political context, method preferences, |the use of multiple rather than single evaluative studies and ways to invigorate evaluation as a culture through avoiding certain kinds of method debates, through encouraging certain kinds of evaluation theory debates and through encouraging evaluators to think of themselves as substantive topic experts capable of generalizing from studies about what seems to work in a given substantive area.