When is the Wilcoxon–Mann–Whitney procedure a test of location? Implications for effect-size measures

The Wilcoxon–Mann–Whitney procedure is invariant under monotone transformations but its use as a test of location or shift is said not to be so. It tests location only under the shift model, the assumption of parallel cumulative distribution functions (cdfs). We show that infinitely many monotone transformations of the measured variable produce parallel cdfs, so long as the original cdfs intersect nowhere or everywhere. Thus there are infinitely many effect sizes measured as shifts of medians, invalidating the notion that there is one true shift parameter and thereby rendering any single estimate dubious. Measuring effect size using the probability of superiority alleviates this difficulty.     

From “4Rs and 2Ss” to “Amaka Amasanyufu” (Happy Families): Adapting a U.S.-based Evidence-Based Intervention to the Uganda Context

In Uganda, one in five children presents mental health challenges, including disruptive behavior disorders (DBDs). DBDs can persist through adulthood and result in negative outcomes. Effective interventions for DBDs have been developed and tested in high-poverty communities in developed countries. Yet, most African countries, such as Uganda, lack such interventions. This paper describes the adaptation process of an evidence-based intervention of U.S. origin to optimize fit to context with intervention fidelity, as part of a randomized trial conducted with youth that exhibit behavioral challenges and their caregivers in 30 schools in Uganda. The process involved: initial meetings with headteachers and teachers to introduce the study and the main concepts of the intervention; initial manual review focusing on 4Rs and 2Ss content by the Uganda team; engagement of community stakeholders for additional feedback on content and cultural relevance; final revision of the manual; and collection of children’s drawings for the illustration of the manual. This paper describes both similarities and differences between the original and adapted intervention content and methods of delivery. The findings also highlight the importance of involving community stakeholders in the adaptation process.     

Mental simulation inflates performance estimates for physical abilities

In five experiments, we examined how mental simulation of physical activities affected estimates of one's ability to perform the same activities. In Experiment 1, participants who simulated lifting aheavy object estimated that they could lift more weight than did participants who did not perform the simulation. In Experiment 2A, the frequency with which participants performed the simulation exercises was manipulated. In Experiments 2B and 2C, we manipulated the amount of weight that people simulated lifting in order to address potential alternative explanations of the inflation effect. In Experiment 3, mental simulations were manipulated within subjects. In all the experiments, the simulated events showed inflated estimates, as compared with nonsimulated events. These results were interpreted in the context of the misattribution-of-familiarity account of imagination inflation.     

A Light Theory with Heavy Burdens

In “ A Light Theory of Color”, Walter Sinnott-Armstrong and David Sparrow argue that color is neither a primary quality of objects, nor a disposition that objects have, nor a property of our visual fields. Rather, according to the view they present, color is a property of light. The present paper aims to show, first, that the light theory is vulnerable to many of the very same objections that Sinnott-Armstrong and Sparrow raise against rival views. Second, the paper argues that the strategies that Sinnott-Armstrong and Sparrow use to avoid certain objections are also available to proponents of rival accounts. This might only seem to show that the light theory is in the same shaky boat as other theories: suffering from the same problems but having the same tools for solving them. The paper concludes with a suggestion as to why this is not the case, but why the existence of the light theory is nevertheless likely to bring increased clarity to the debate about color realism.     

Dying to be thin: the effects of mortality salience and body mass index on restricted eating among women

Following terror management theory, the authors suggest women's striving to attain a thin physique is fueled in part by existential concerns. In three studies, women restricted consumption of a nutritious but fattening food in response to reminders of mortality (mortality salience; MS). When conducted in private (Study 1), this effect was found among women but not men; when replicated in a group setting in which social comparison was likely (Studies 2 and 3), only women who were relatively less successful attaining the thin ideal (i.e., high body mass index; BMI) restricted eating after MS. In Study 3, MS caused high BMI women to perceive themselves as more discrepant from their ideal thinness; this perceived failure mediated the effects of MS and BMI on eating behavior. Findings are discussed from a self-regulatory framework, which considered in the context of pressures for women to be thin, can shed light on health risk behavior.