Motivation as a function of success frequency

Motivation and Emotion - It is well-established that intermediate challenge is optimally motivating. We tested whether this can be quantified into an inverted-U relationship between motivation and...     

Reliability and validity of a twelve-minute walking test for coronary heart disease patients

This study examined the reliability and validity of a 12-min. walking test for coronary heart disease patients. CHD patients (28 men, 18 women) were recruited out of 86 CHD patients of the Martini Hospital Groningen, The Netherlands. 46 CHD patients (age M=66.0 yr., SD=6.8) participated in the reliability study and 24 (age M=62.0 yr., SD=9.2) in the validity study. A test-retest analysis showed a satisfactory Bland-Altman plot and an intraclass coefficient of .98. The Pearson correlation between the score on the test and the VO2 peak was .77. This test gives a reliable and valid assessment of cardiorespiratory fitness of CHD patients.     

Treatment Sensitivity of a Brief Rating Scale for Attention-Deficit Hyperactivity Disorder (ADHD) Symptoms

This study examined the treatment sensitivity of the ADHD Questionnaire (ADHD-Q), which is a brief rating scale for measuring symptoms of inattention, hyperactivity, and impulsivity in children. Parent, teacher, and child self-report data of the ADHD-Q were obtained for 17 clinically referred children with ADHD on the three occasions: (1) during the regular intake assessment, (2) just before the start of the stimulant medication (i.e., methylphenidate) intervention, and (3) four weeks after the start of the medication intervention. Results showed that ADHD-Q scores remained fairly stable in the period prior to the intervention, but then showed a substantial decline after the stimulant medication had been administered. Clearly, this finding supports the treatment sensitivity of the ADHD-Q.     

Temporal factors in resource dilemmas

The conflict between present and future consumption lies at the heart of resource dilemmas (RDs), yet the role of time has received little attention in this research area. Emphasis was on factors related to the social rather than the temporal conflict inherent in an RD. We propose a model that deals explicitly with the temporal distribution of outcomes. The model combines three basic elements: a simple algebraic model, representing the RD's payoff structure; a growth function, reflecting the autonomous growth of the resource pool; and a discount function, describing how the temporal distance of outcomes affects their perceived value. The model provides a comprehensive framework for understanding the role of temporal factors in RD situations. It enables us to identify four relevant temporal RD characteristics (people's discount rates, their time horizon, the inter-trial delay, and the pool's growth rate) and to describe how these would be expected to affect people's tendency to cooperate. Theoretical, methodological and practical implications of the work are briefly discussed.     

Stability of nonlinear principal components analysis: an empirical study using the balanced bootstrap

Principal components analysis (PCA) is used to explore the structure of data sets containing linearly related numeric variables. Alternatively, nonlinear PCA can handle possibly nonlinearly related numeric as well as nonnumeric variables. For linear PCA, the stability of its solution can be established under the assumption of multivariate normality. For nonlinear PCA, however, standard options for establishing stability are not provided. The authors use the nonparametric bootstrap procedure to assess the stability of nonlinear PCA results, applied to empirical data. They use confidence intervals for the variable transformations and confidence ellipses for the eigenvalues, the component loadings, and the person scores. They discuss the balanced version of the bootstrap, bias estimation, and Procrustes rotation. To provide a benchmark, the same bootstrap procedure is applied to linear PCA on the same data. On the basis of the results, the authors advise using at least 1,000 bootstrap samples, using Procrustes rotation on the bootstrap results, examining the bootstrap distributions along with the confidence regions, and merging categories with small marginal frequencies to reduce the variance of the bootstrap results.     

Example‐based learning: Effects of model expertise in relation to student expertise

Background. Worked examples are very effective for novice learners. They typically present a written‐out ideal (didactical) solution for learners to study. Aims. This study used worked examples of patient history taking in physiotherapy that presented a non‐didactical solution (i.e., based on actual performance). The effects of model expertise (i.e., worked example based on advanced, third‐year student model or expert physiotherapist model) in relation to students' expertise (i.e., first‐ or second‐year) were investigated. Sample. One hundred and thirty‐four physiotherapy students (61 first‐year and 73 second‐year). Methods. Design was 2×2 factorial with factors ‘Student Expertise’ (first‐year vs. second‐year) and ‘Model Expertise’ (expert vs. advanced student). Within expertise levels, students were randomly assigned to the Expert Example or the Advanced Student Example condition. All students studied two examples (content depending on their assigned condition) and then completed a retention and test task. They rated their invested mental effort after each example and test task. Results. Second‐year students invested less mental effort in studying the examples, and in performing the retention and transfer tasks than first‐year students. They also performed better on the retention test, but not on the transfer test. In contrast to our hypothesis, there was no interaction between student expertise and model expertise: all students who had studied the Expert examples performed better on the transfer test than students who had studied Advanced Student Examples. Conclusions. This study suggests that when worked examples are based on actual performance, rather than an ideal procedure, expert models are to be preferred over advanced student models.     

Diagnostic validity of the Eppendorf Schizophrenia Inventory (ESI): a self-report screen for ultrahigh risk and acute psychosis

Providers of mental health services need tools to screen for acute psychosis and ultrahigh risk (UHR) for transition to psychosis in help-seeking individuals. In this study, the Eppendorf Schizophrenia Inventory (ESI) was examined as a screening tool and for its ability to correctly predict diagnostic group membership (e.g., help seeking, mild psychiatric complaints, highly symptomatic mood or anxiety disorder, UHR, acute psychosis). Diagnostic evaluation with established instruments was used for diagnosis in 3 research samples. UHR status was assessed with the Structured Interview for Prodromal Symptoms/Scale of Prodromal Symptoms (Miller et al., 1999) and the Bonn Scale for the Assessment of Basic Symptoms Prediction list (Gross, Huber, Klosterk?tter, & Linz, 1987; Klosterk?tter, Hellmich, Steinmeyer, & Schulze-Lutter, 2001). This study showed that members of different diagnostic groups rate themselves significantly differently on the ESI and its subscales. A new subscale was constructed, the UHR-Psychosis scale, that showed good utility in detecting individuals with interview-diagnosed UHR status and acute psychosis. The scale is also sensitive to the threshold between UHR and acute psychosis. Practical applications of the ESI include use as a diagnostic tool within various settings.