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941.
The winner's curse phenomenon refers to the fact that the winner in a common value auction, in order to actually win the auction, is likely to have overestimated the item's value and consequently is likely to gain less than expected and may even lose (i.e., it is said to be “cursed”). Past research, using the “Acquiring a company” task has shown that people do not overcome this bias even after they receive extensive feedback. We suggest that the persistence of the winner's curse is due to a combination of two factors: variability in the environment that leads to ambiguous feedback (i.e., choices and outcomes are only partially correlated) and the tendency of decision makers to learn adaptively. We show in an experiment that by reducing the variance in the feedback, performance can be significantly improved. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
942.
Experiments on three two‐person threshold public good provision games, namely, the simultaneous, sequential, and dictator games, are conducted to explore the motives behind giving. Players who move simultaneously are endowed with equal bargaining power, and players who move first are endowed with more bargaining power than players who move subsequently. Dictators are indubitably endowed with complete bargaining power. Since the differences between the bargaining powers of two players increase from the simultaneous to the sequential to the dictator game, comparisons among games allow us to trace whether the contribution behavior is motivated by fairness or is simply due to the strategic concern. The experimental evidence shows that the strategic concern explains the overall contribution behavior better than the motive of fairness. However, in the final round 26% of the dictators share the threshold evenly with their opponents, suggesting that some subjects do play fairly. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
943.
This article is an exposition of deep or critical multiculturalism that is grounded in a mutually respectful dialogue. Such multiculturalism names historical oppressions, recognizes the structural causes of injustice and inequality, and is profoundly open to cultural critique, challenge and change. In order to promote such a multicultural practice, the article makes the case for a dialogical politics of deep and mutual respect in which ethno‐religious sensibilities are validated and welcomed in their rich diversity. In doing so, the article draws upon the author's empirical research on the Muslim minority in contemporary Canada. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
944.
945.
Research suggests that, in some cases, mechanical restraints may function as positive reinforcers. In this study, we conducted a functional analysis of severe aggression exhibited by an individual with a history of wearing arm splints. The results of this functional analysis demonstrated that his aggression was maintained by access to the arm splints. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
946.
Recently, R. D. Stoel, F. G. Garre, C. Dolan, and G. van den Wittenboer (2006) reviewed approaches for obtaining reference mixture distributions for difference tests when a parameter is on the boundary. The authors of the present study argue that this methodology is incomplete without a discussion of when the mixtures are needed and show that they only become relevant when constrained difference tests are conducted. Because constrained difference tests can hide important model misspecification, a reliable way to assess global model fit under constrained estimation would be needed. Examination of the options for assessing model fit under constrained estimation reveals that no perfect solutions exist, although the conditional approach of releasing a degree of freedom for each active constraint appears to be the most methodologically sound one. The authors discuss pros and cons of constrained and unconstrained estimation and their implementation in 5 popular structural equation modeling packages and argue that unconstrained estimation is a simpler method that is also more informative about sources of misfit. In practice, researchers will have trouble conducting constrained difference tests appropriately, as this requires a commitment to ignore Heywood cases. Consequently, mixture distributions for difference tests are rarely appropriate.  相似文献   
947.
There is controversy about whether mindfulness-based approaches to psychotherapy represent a new wave of cognitive-behavioral therapy or a core process in all psychotherapies. One way of conceptualizing mindfulness is in terms of emotion regulation; mindfulness is a strategy aimed at opposing suppression and avoidance. Dispositional mindfulness has been associated with greater activation in prefrontal cortex and greater deactivation of amygdala during affect labeling. A number of rigorous studies of mindfulness-based cognitive therapy for depression have been positive. However, much remains to be discovered about the underlying mechanisms of and clinical indications for mindfulness-based approaches.  相似文献   
948.
The aim of the present study was to assess the effects of daily stress perception on cognitive performance and morning basal salivary cortisol and alpha-amylase levels in healthy children aged 9-12. Participants were classified by whether they had low daily perceived stress (LPS, n = 27) or a high daily perceived stress (HPS, n = 26) using the Children Daily Stress Inventory (CDSI). Salivary cortisol and alpha-amylase were measured at awakening and 30 minutes later. Cognitive performance was assessed using the Cognitive Drug Research assessment system. The HPS group exhibited significantly poorer scores on speed of memory (p < .05) and continuity of attention (p < .05) relative to the LPS group. The HPS group also showed significantly lower morning cortisol levels at awakening and at +30 minutes measures in comparison with the LPS group (p < .05), and mean morning cortisol levels were negatively correlated with speed of memory (p < .05) in the 53 participants. No significant differences were observed between both groups in alpha-amylase levels. These findings suggest that daily perceived stress in children may impoverish cognitive performance via its modulating effects on the HPA axis activity.  相似文献   
949.
The sexual and reproductive health (SRH)-related needs of people living with HIV/AIDS (PLHA) have not been sufficiently recognised in research and clinical care. Fifteen study sites in 13 European countries participated in this qualitative study to assess differences in perceptions between service providers (SP) and PLHA on SRH-related problems and needs of PLHA. Factors influencing SRH were determined to collect evidence on how to improve service provision. Qualitative data were obtained using an interpretative ethnographical approach. Data were analysed inductively on country level; a cross country data matrix was developed to facilitate the contextual analysis. Thirty-seven FGD discussions were organised with a total of 254 participants. A short survey was distributed to assess demographic characteristics. Results revealed insufficient information and lack of behavioural skills regarding SRH issues among PLHA. Intra- and interpersonal, provider-related, and social factors were found to influence the SRH behaviours of PLHA. Although from patients' perception SRH is a prioritized issue, it rarely comes up during routine HIV clinical care. SP need adequate counseling training to tackle SRH-related issues. A better integration between HIV care programs and SRH care settings is needed to improve effective service provision.  相似文献   
950.
从李丽云事件看生命健康权、患者自主权和医生干涉权   总被引:2,自引:0,他引:2  
当患方行使自主权所做的决定危及自身生命健康权时,能否赋予医生干涉权以实现生命高于一切的理念?阐明了生命健康权、患者自主权和医生干涉权的关系.并从我国实际出发,论述不能通过赋予医生干涉权来避免类似李丽云悲剧的发生,建议立法完善对民事行为能力的规定,建立司法机关或其他第三方机构提前快速审查机制来解决自主权与生命权的冲突。  相似文献   
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