Behavior Ratings and Observations of Externalizing Symptoms in Girls: The Role of Child Popularity with Adults

This study examined staff ratings and live observations of externalizing behavior in 149 girls with and without attention-deficit/hyperactivity disorder (ADHD), who participated in all-female naturalistic research camps. Girls' popularity with adult camp staff was hypothesized to explain discrepancies between ratings and observations. Compared to behavior observations, staff ratings overestimated the externalizing behavior of girls who were disliked by staff. In contrast, ratings and observations were consistent for girls who were liked by staff. Among girls who were disliked by staff, unpopularity with peers predicted a larger discrepancy between staff ratings and observations, but peer status made little difference in rating–observation discrepancies of girls liked by staff. All results held after controlling for the participants' ADHD versus comparison status. Results suggest that staff ratings may be biased by personal feelings about children and that direct observations may be more immune to such bias.     

Sensitivity to number: Reply to Gebuis and Gevers

Past research showing a bias towards the larger non-symbolic number by adults and children in line bisection tasks (de Hevia & Spelke, 2009) has been challenged by Gebuis and Gevers, suggesting that area subtended by the stimulus and not number is responsible for the biases. I review evidence supporting the idea that although sensitivity to number might be relatively affected by visual cues, number is a major, salient property of our environment. The influence of non-numerical cues might be seen as the concurrent processing of dimensions that entail information of magnitude, without implying that number is constructed out of those dimensions.     

Sample diversity and premise typicality in inductive reasoning: evidence for developmental change

Evaluating whether a limited sample of evidence provides a good basis for induction is a critical cognitive task. We hypothesized that whereas adults evaluate the inductive strength of samples containing multiple pieces of evidence by attending to the relations among the exemplars (e.g., sample diversity), six-year-olds would attend to the degree to which each individual exemplar in a sample independently appears informative (e.g., premise typicality). To test these hypotheses, participants were asked to select between diverse and non-diverse samples to help them learn about basic-level animal categories. Across various between-subject conditions (N=133), we varied the typicality present in the diverse and non-diverse samples. We found that adults reliably selected to examine diverse over non-diverse samples, regardless of exemplar typicality, six-year-olds preferred to examine samples containing typical exemplars, regardless of sample diversity, and nine-year-olds were somewhat in the midst of this developmental transition.     

Inventor perseverance after being told to quit: the role of cognitive biases

We find that approximately one third (29%) of independent inventors continue to spend money and 51% continue to spend time on projects after receiving highly diagnostic advice to cease effort. Using survey data from actual inventors, this paper studies the role of overconfidence, optimism, and the sunk‐cost bias in these decisions. We find that inventors are more overconfident and optimistic than the general population. We also find that optimism and past expenditures increased perseverance after being told to quit, while overconfidence in judgment ability had no effect. After being told to quit, optimists spend 166% more than pessimists and those having already spent, for example, $10 000 spend another $10 000. Copyright © 2007 John Wiley & Sons, Ltd.     

Cognitive aspects of nonclinical obsessive-compulsive hoarding

Research on the cognitive variables associated with obsessive-compulsive hoarding is scarce. In this study, we investigated cognitive variables that may contribute to the maintenance and possibly etiology of hoarding. College students who characterized themselves as either "packrats" (nonclinical hoarders; n=21) or not (control participants; n=20) completed questionnaires assessing hoarding behavior and beliefs about hoarding, and completed a task requiring them to categorize diverse objects and trinkets of minimal value into groups. The results revealed that nonclinical hoarders, relative to control participants, rated the categorization task as significantly more stressful and difficult. Relative to control participants, hoarders took longer to complete the task and sorted objects into more categories. These findings suggest that underinclusiveness and indecisiveness, characteristic of clinical hoarders, are evident in nonclinical hoarders as well.     

I blush, therefore I will be judged negatively: influence of false blush feedback on anticipated others’ judgments and facial coloration in high and low blushing-fearfuls

In the present study, we investigate whether people attribute costs to displaying a blush. Individuals with and without fear of blushing were invited to have a short conversation with two confederates. During the conversation, half of the individuals received the feedback that they were blushing intensely. The study tested whether the belief that one is blushing leads to the anticipation that one will be judged negatively. In addition, the set-up permitted the actual physiological blush response to be investigated. In line with the model that we propose for erythrophobia, participants in the feedback condition expected the confederates to judge them relatively negatively, independent of their fear of blushing. Furthermore, sustaining the idea that believing that one will blush can act as a self-fulfilling prophecy, high-fearfuls showed relatively intense facial coloration in both conditions, whereas low-fearfuls only showed enhanced blush responses following false blush feedback.     

Learning How to Generalize

Generalization is a fundamental problem solved by every cognitive system in essentially every domain. Although it is known that how people generalize varies in complex ways depending on the context or domain, it is an open question how people learn the appropriate way to generalize for a new context. To understand this capability, we cast the problem of learning how to generalize as a problem of learning the appropriate hypothesis space for generalization. We propose a normative mathematical framework for learning how to generalize by learning inductive biases for which properties are relevant for generalization in a domain from the statistical structure of features and concepts observed in that domain. More formally, the framework predicts that an ideal learner should learn to generalize by either taking the weighted average of the results of generalizing according to each hypothesis space, with weights given by how well each hypothesis space fits the previously observed concepts, or by using the most likely hypothesis space. We compare the predictions of this framework to human generalization behavior with three experiments in one perceptual (rectangles) and two conceptual (animals and numbers) domains. Across all three studies we find support for the framework's predictions, including individual‐level support for averaging in the third study.