Thinking around the corner: the development of planning abilities

The ability to plan and search ahead is essential for problem solving in most situations in everyday life. To investigate the development of planning and related processes, a sample of four- and five-year-old children was examined in a variant of the Tower of London, a frequently used neuropsychological assessment tool of planning abilities. The applied problems either required searching ahead for optimal solution or were solvable by pure step-by-step forward processing. Furthermore, the ambiguity of subgoal ordering was varied.Results revealed an age-related effect of search depth: the four-year olds’ planning accuracy was particularly decreased in problems demanding search ahead, while five-year olds mastered both problem types equally well. Interestingly, this interaction between age and search depth could not be accounted for by measures of working memory and inhibition. Differential effects of age were also found for subgoal ordering with respect to initial planning and movement execution times. In sum, planning abilities showed considerable development during late kindergarten age that appeared to be specifically associated with the integration and back-validation of the anticipated consequences of internally modeled actions. The present study demonstrates that a careful consideration of problem structure may greatly enhance the insights gained from the application of a routinely used assessment tool, the Tower of London. This may be especially advantageous when addressing specific subpopulations such as children or clinical samples.     

Perfectionism in school teachers: relations with stress appraisals, coping styles, and burnout

Many school teachers suffer from stress and burnout, and perfectionism is a personality characteristic that has been associated with increased stress, maladaptive coping, and burnout. Recent findings, however, show that perfectionism has both positive and negative facets. To investigate how these facets are related to stress, coping, and burnout in teachers, a sample of 118 secondary school teachers completed multidimensional measures of perfectionism, stress appraisals, coping styles, and burnout. Multiple regression analyses showed that striving for perfection was positively related to challenge appraisals and active coping and inversely to threat/loss appraisals, avoidant coping, and burnout whereas negative reactions to imperfection were positively related to threat/loss appraisals, avoidant coping, and burnout and inversely to challenge appraisals and active coping. Perceived pressure to be perfect showed differential relationships depending on the source of pressure: Whereas pressure from students was positively related to loss appraisals and pressure from students' parents was positively related to burnout, pressure from colleagues was inversely related to threat appraisals and burnout. The findings suggest that striving for perfection and perceived pressure from colleagues do not contribute to stress and burnout in teachers, whereas negative reactions to imperfection and perceived pressure from students and students' parents may be contributing factors.     

Estimating long-range dependence in time series: An evaluation of estimators implemented in R

Recent studies have shown that many physiological and behavioral processes can be characterized by long-range correlations. The Hurst exponent H of fractal analysis and the fractional-differencing parameter d of the ARFIMA methodology are useful for capturing serial correlations. In this study, we report on different estimators of H and d implemented in R, a popular and freely available software package. By means of Monte Carlo simulations, we analyzed the performance of (1) the Geweke—Porter-Hudak estimator, (2) the approximate maximum likelihood algorithm, (3) the smoothed periodogram approach, (4) the Whittle estimator, (5) rescaled range analysis, (6) a modified periodogram, (7) Higuchi’s method, and (8) detrended fluctuation analysis. The findings—confined to ARFIMA (0, d, 0) models and fractional Gaussian noise—identify the best estimators for persistent and antipersistent series. Two examples combining these results with the step-by-step procedure proposed by Delignières et al. (2006) demonstrate how this evaluation can be used as a guideline in a typical research situation.     

The Psychology (and Economics) of Trust

Interpersonal trust is a mental construct with implications for social functioning and economic behavior. We review contemporary theories of trust from behavioral economics and social psychology. Neoclassical economic theory considers trust in strangers to be irrational, but observed behavior reveals widespread trust and trustworthiness. Theories of social preferences and adherence to social norms have been proposed to rationalize trust. Psychological approaches investigate trusting behavior in terms of an underlying disposition, intergroup processes, and cognitive expectations. The breadth of these approaches illustrates the multi‐faceted nature of trusting behavior. The determinants of trust are related to the relevant characteristics of the individual, the situation, and their interaction.     

Liking persons versus liking groups: a dual-process hypothesis

Most research on liking of persons and groups has been conducted within separate paradigms, but the implicit assumption has been that the same processes govern judgments of liking or disliking regardless of the nature of the target. Departing from this assumption, we suggest a dual-process hypothesis according to which people base their liking of a target person primarily on the desirability of the person's characteristics, whereas they base their liking of a group primarily on the degree of similarity between the group and themselves. To test this hypothesis, participants were presented with either positively or negatively valenced sketches that either described an individual person or a group of people. Path analyses revealed that liking of a person was best predicted by desirability ratings, whereas liking of a group was best predicted by similarity ratings. Implications of these findings for stereotype maintenance are discussed. © 1998 John Wiley & Sons, Ltd.