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181.
182.
The negative thoughts that anxious children experience while sitting for an exam consume working memory resources at the cost of resources for performing on the exam. In a randomized field experiment (N = 117) with primary school students, we investigated the hypothesis that stimulating students to look through the problems of a math test before they start solving them would reduce anxiety, release these anxiety‐related working memory resources, and lead to higher test performance than not allowing students to look ahead in the test. The results confirmed the hypothesis, indicating that the positive effects of looking ahead applied to all students, regardless of their anxiety level (low, medium, or high). The results suggest that by looking ahead in a test, less working memory resources are consumed by intrusive thoughts, and consequently, more resources can be used for performing on the test. Theoretical and practical implications of the results are discussed. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
183.
This paper argues that trustworthiness is an epistemic virtue that promotes objectivity. I show that untrustworthy imposture can be an arrogant act of privilege that silences marginalized voices. But, as epistemologists of ignorance have shown, sometimes trickery and the betrayal of epistemic norms are important resistance strategies. This raises the question: when is betrayal of trust epistemically virtuous? After establishing that trust is central to objectivity, I argue for the following answer: a betrayal is epistemically vicious when it strengthens or promotes oppressive, exclusive networks of trust, and a betrayal is epistemically virtuous when it expands trust networks to involve the oppressed. These criteria correctly account for both the epistemic vice of a recent case of Internet imposture and the epistemic virtue of resistant tricksters.  相似文献   
184.
185.
The search for different options before making a consequential choice is a central aspect of many important decisions, such as mate selection or purchasing a house. Despite its importance, surprisingly little is known about how search and choice are affected by the observed and objective properties of the decision problem. Here, we analyze the effects of two key properties in a binary choice task: the options' observed and objective values, and the variability of payoffs. First, in a large public data set of a binary choice task, we investigate how the observed value and variability relate to decision‐makers' efforts and preferences during search. Furthermore, we test how these properties influence the chance of correctly identifying the objectively maximizing option, and how they affect choice. Second, we designed a novel experiment to systematically analyze the role of the objective difference between the options. We find that a larger objective difference between options increases the chance for correctly identifying the maximizing option, but it does not affect behavior during search and choice. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
186.
隆乳术不仅可以重塑女性的形体美,而且可以增强女性的自信心,在当前具有广阔的市场。纵观隆乳术的发展演变史,从最初的注射隆乳术到自体组织隆乳术,再到当前的假体隆乳术和自体脂肪移植隆乳术,经历了“实践、认识、再实践、再认识”的多次反复。各种隆乳方式各具特色,其间既有成功的经验,又有失败的教训。针对隆乳术安全性的改进推动了隆乳术的不断向前发展。寻找一种安全有效的隆乳方式和理想的隆乳材料成为当前隆乳术发展的关键和整形外科医师关注的重点。  相似文献   
187.
Crime linkage and the investigation of behavioural consistency amongst serial offenders has been a flourishing field of research over the past decade or so, especially with respect to serial sex offenders. The emerging research in this field has often portrayed serial sex offenders as a single, distinct, and homogeneous group. Such an assumption, however, has never been empirically examined. Using a criminal career approach and a sample of 72 serial sex offenders who have committed a total of 361 sexual assaults on stranger victims, the current study aims to examine and describe subgroups of crime series patterns amongst serial sex offenders in terms of duration and frequency of offending. The level of environmental consistency display (i.e. offender's choice of crime location and characteristics of the crime site selected) across subgroups of crime series patterns is also examined. Study findings suggest the presence and heterogeneity of crime series patterns amongst serial sex offenders, advocating for the consideration of subgroups of crime series patterns when studying serial sex offenders. Moreover, the offenders' level of environmental consistency varies across the different crime series patterns identified, allowing for the identification of subgroups of offenders showing a higher or lower level of environmental consistency. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
188.
The dual systems model of adolescent risk‐taking portrays the period as one characterized by a combination of heightened sensation seeking and still‐maturing self‐regulation, but most tests of this model have been conducted in the United States or Western Europe. In the present study, these propositions are tested in an international sample of more than 5000 individuals between ages 10 and 30 years from 11 countries in Africa, Asia, Europe and the Americas, using a multi‐method test battery that includes both self‐report and performance‐based measures of both constructs. Consistent with the dual systems model, sensation seeking increased between preadolescence and late adolescence, peaked at age 19, and declined thereafter, whereas self‐regulation increased steadily from preadolescence into young adulthood, reaching a plateau between ages 23 and 26. Although there were some variations in the magnitude of the observed age trends, the developmental patterns were largely similar across countries.  相似文献   
189.
Verb learning is difficult for children (Gentner, 1982 ), partially because children have a bias to associate a novel verb not only with the action it represents, but also with the object on which it is learned (Kersten & Smith, 2002 ). Here we investigate how well 4‐ and 5‐year‐old children (N = 48) generalize novel verbs for actions on objects after doing or seeing the action (e.g., twisting a knob on an object) or after doing or seeing a gesture for the action (e.g., twisting in the air near an object). We find not only that children generalize more effectively through gesture experience, but also that this ability to generalize persists after a 24‐hour delay.  相似文献   
190.
To harness the complexity of their high‐dimensional bodies during sensorimotor development, infants are guided by patterns of freezing and freeing of degrees of freedom. For instance, when learning to reach, infants free the degrees of freedom in their arm proximodistally, that is, from joints that are closer to the body to those that are more distant. Here, we formulate and study computationally the hypothesis that such patterns can emerge spontaneously as the result of a family of stochastic optimization processes, without an innate encoding of a maturational schedule. In particular, we present simulated experiments with an arm where a computational learner progressively acquires reaching skills through adaptive exploration, and we show that a proximodistal organization appears spontaneously, which we denote PDFF (Proximo Distal Freezing and Freeing of degrees of freedom). We also compare this emergent organization between different arm morphologies—from human‐like to quite unnatural ones—to study the effect of different kinematic structures on the emergence of PDFF.  相似文献   
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