The effects of wording on the understanding and use of uncertainty information in a threshold forecasting decision

Many believe that information about small chances of severe weather would be useful to the general public for precautionary action. What is the best way to explain this kind of information to a non‐expert audience? The studies reported here investigated effects of framing (negative vs. positive), format (frequency vs. probability), likelihood (low vs. high) and compatibility (task‐match) on interpretation of verbal expressions of forecast uncertainty and on subsequent forecasting decisions. The crucial factor was the match between the verbal expression and the overall task goal. Errors increased when there was a mismatch between the expression (e.g. winds less than 20 knots) and the task (e.g. post an advisory when winds will exceed 20 knots). However, framing and format had little impact. We conclude that consideration of user expectations arising from the overall task goal is crucial in explaining uncertainty information to a naïve audience. Global expectations overpower other potential effects. Copyright © 2008 John Wiley & Sons, Ltd.     

What coping tells about personality

In this study, 123 participants (non‐psychology students) who responded to an interpersonal stress situation staged in the laboratory were judged by unacquainted observers in terms of the Big Five dimensions, intelligence and social attractiveness. Coping behaviour appeared to predict personality impressions in a way that mirrors the relations between personality and coping observed in previous research: Overall, higher levels of Extraversion (E), Agreeableness (A), Conscientiousness (C) and Openness to experience (O) (as well as intelligence and social attractiveness) were predicted by problem‐focussed behaviour and cognitive restructuring, whereas higher levels of Neuroticism (N) were predicted by withdrawal/passivity. The interpersonal impact of the particular coping reactions, as indicated by a positive personality impression, were largely inconsistent with their impact on affect following the stress induction. Copyright © 2009 John Wiley & Sons, Ltd.     

Better safe than sorry: Precautionary reasoning and implied dominance in risky decisions

In four studies, student and nonstudent participants evaluated the possible outcomes of binary decisions involving health, safety, and environmental risks (e.g., whether to issue a dam‐failure evacuation order). Many participants indicated that false positives (e.g., evacuation, but no dam failure) were better than true negatives (e.g., no evacuation and no dam failure), thereby implying that the more protective action dominated the less protective action. A common rationale for this response pattern was the precautionary maxim “better safe than sorry.” Participants apparently evaluated outcomes partly on the basis of the decisions that might lead to them, in conflict with consequentialist decision models. Consistent with this explanation, the prevalence of implied dominance decreased substantially when the emphasis on decisions was reduced. These results demonstrate that an initial preference for a decision alternative can alter the evaluation of possible consequences of both the preferred alternative and a competing alternative, suggesting positive feedback loops that reinforce the initial preference. The rationality of considering the decision itself as an attribute of possible outcomes is discussed. Copyright © 2009 John Wiley & Sons, Ltd.     

The listener's temperament and perceived tempo and loudness of music

The relationship between the listener's temperament and perceived magnitude of tempo and loudness of music was studied using the techniques of magnitude production, magnitude estimation scaling and cross‐modal matching. Four piano pieces were presented at several levels of tempo and loudness. In Study 1, participants adjusted tempo and loudness of music to their subjective level of comfort. In Study 2, participants estimated these parameters on a numerical scale and matched the length of a line segment to the estimates of these musical features. The results showed significant correlations of selected aspects of perceived tempo with perseveration and endurance as well as of selected aspects of perceived loudness with endurance and emotional reactivity. Perceived tempo and loudness, as measured by magnitude production and cross‐modal matching tasks, do not seem to systematically correlate with the six formal characteristics of behaviour distinguished in the most recent version of the Regulative Theory of Temperament (RTT). Additionally, there is some evidence that they are selectively associated with reactivity and activity, the dimensions of a previous version of the RTT. The study extends the methodology of research on music preferences and the stimulatory value of music. Copyright © 2009 John Wiley & Sons, Ltd.     

Optimum sample size allocation to minimize cost or maximize power for the two‐sample trimmed mean test

When planning a study, sample size determination is one of the most important tasks facing the researcher. The size will depend on the purpose of the study, the cost limitations, and the nature of the data. By specifying the standard deviation ratio and/or the sample size ratio, the present study considers the problem of heterogeneous variances and non‐normality for Yuen's two‐group test and develops sample size formulas to minimize the total cost or maximize the power of the test. For a given power, the sample size allocation ratio can be manipulated so that the proposed formulas can minimize the total cost, the total sample size, or the sum of total sample size and total cost. On the other hand, for a given total cost, the optimum sample size allocation ratio can maximize the statistical power of the test. After the sample size is determined, the present simulation applies Yuen's test to the sample generated, and then the procedure is validated in terms of Type I errors and power. Simulation results show that the proposed formulas can control Type I errors and achieve the desired power under the various conditions specified. Finally, the implications for determining sample sizes in experimental studies and future research are discussed.     

The maximum priority index method for severely constrained item selection in computerized adaptive testing

This paper introduces a new heuristic approach, the maximum priority index (MPI) method, for severely constrained item selection in computerized adaptive testing. Our simulation study shows that it is able to accommodate various non‐statistical constraints simultaneously, such as content balancing, exposure control, answer key balancing, and so on. Compared with the weighted deviation modelling method, it leads to fewer constraint violations and better exposure control while maintaining the same level of measurement precision.     

An effect size index for comparing two independent alpha coefficients

Since Cronbach proposed the α coefficient in 1951, researchers have contributed to the derivation of its sampling distribution and the testing of related statistical hypotheses. Yet, there has been no research on effect size index relevant to coefficient α to our knowledge. Considering the importance of effect size in understanding quantitative research findings, we therefore developed an effect size index Δ for the comparison of two independent αs with equal test length based on the asymptotic distribution of under the assumptions of normality and compound symmetry. Simulations indicated that the index was applicable when the sample size was at least 100. The robustness of the derived index when the required assumptions were violated was also explored. It is suggested that the index should be applicable in most cases of unequal test lengths and could be extended to non‐normally distributed component scores. Moreover, a small simulation was conducted to explore the behaviour of Δ with correlated errors, a frequently studied situation violating the assumption of compound symmetry. The proposed index was found to be robust unless a large number of highly correlated errors were present in the data.     

Decomposing self‐estimates of intelligence: Structure and sex differences across 12 nations

This study examines the structure of self‐estimates of intelligence (SEI) across 12 nations (Australia, Austria, Brazil, France, Iran, Israel, Malaysia, South Africa, Spain, Turkey, UK and US). Participants rated themselves on general and specific abilities from three popular models of intelligence: Gardner's multiple intelligences, Sternberg's triarchic theory of intelligence, and Goleman's emotional intelligence. The results showed that (a) laypeople across nations have similar and invariant concepts of intelligence, (b) concepts of intelligence are cross‐culturally closely related to academic notions of intellectual ability and (c) sex differences in general and specific SEI favouring men are consistent across countries. Male hubris and female humility in SEI seem independent of sex differences in actual cognitive ability and national levels of masculinity‐femininity. Furthermore, international mean differences in general SEI could not be attributed to discrepancies in national intelligence quotient (IQ) levels or to cultural variations.     

Improving self‐regulated learning of preschool children: Evaluation of training for kindergarten teachers

Background In the context of lifelong learning, self‐regulated learning is an important competence. Children between 4 and 6 years of age are at a crucial step in their life to develop self‐regulatory competence. That is why their kindergarten teachers play an important role as instructors as well as role models. Aim This study tested the effects of self‐regulation training for kindergarten teachers concerning their own self‐regulation and methods to foster self‐regulation in children at preschool age whom they were teaching. Sample In this study, 35 German kindergarten teachers and 97 children participated. All adult participants were graduated kindergarten teachers. Method The kindergarten teachers were tested with a questionnaire 2 weeks before and after the training. At the same time, the preschoolers were interviewed. A waiting control group design was applied. Results and conclusions The results obtained by means of analyses of variance show that the self‐regulation of the kindergarten teachers as well as the self‐regulated learning of preschoolers whose kindergarten teachers took part in the training improved significantly. The results indicate that it is possible to improve self‐regulated learning of preschool children by a training programme for kindergarten teachers.