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861.
This paper studies mixed-gender group interactions in a strategic game where group members are sequentially eliminated till
a single winner takes all. Study 1 tests the hypothesis that female contestants are retained till final rounds where they
are eliminated. Using observational data from the US television show The Weakest Link (20 shows), results show that females are finalists but not winners. In a laboratory study (Study 2, 67 Berkeley undergraduates),
we show that this effect is attenuated when winnings are shared among finalists (versus one winner takes all) due to the reduction
in competitive pressures in the context.
This research was supported in part by the Junior Faculty Research Grant awarded by the University of California at Berkeley
to the second author. 相似文献
862.
不同时程应激对大鼠行为、免疫和交感神经系统反应的影响 总被引:8,自引:0,他引:8
研究旨在研究不同时程情绪应激诱导的大鼠行为、免疫和神经内分泌反应的动态变化及其相互关系。实验采用一种在程序性饮水的固定时间点不确定性给予大鼠空瓶刺激诱发其情绪反应的应激模式,测定不同时程(14,21和28天)应激对大鼠行为、交感神经系统反应、体液免疫功能及体重增长的影响。结果表明,情绪应激导致大鼠攻击行为显著增加,且在整个应激过程中情绪应激组大鼠的攻击行为都被稳定地诱导;不同时程的情绪应激均导致大鼠特异性抗OVA抗体水平明显降低,且降低的程度类似;在情绪应激的第14天和28天应激组大鼠血中去甲肾上腺素水平明显高于对照组,但后者升高的水平明显低于前者。此外,14天应激明显抑制大鼠的体重增长,但随着应激时程的延长,体重增长逐渐恢复。这些结果表明,随着应激时程的延长,大鼠行为、免疫和神经内分泌反应的适应性改变存在时程差异,有助于进一步了解应激诱发的各种反应间的复杂关系 相似文献
863.
亲子性话题沟通风格对青少年性行为和性态度的预测: 依恋的调节效应 总被引:2,自引:0,他引:2
采用问卷法探讨了亲子间性话题沟通风格与青少年性行为、性态度的关系,并考查了亲子依恋的调节效应。结果发现:(1)两个关于性别、父母职业和受教育程度的多元方差分析表明:男生与女生在与父亲和母亲的性话题沟通开放性上均没有显著差异,与父亲和母亲性话题沟通的舒适感上有显著差异。男生与父亲的性话题沟通风格好于与母亲的,而女生与母亲的性话题沟通风格好于与父亲的。父母的职业和受教育程度以及青少年性别、父母职业、受教育程度的交互作用不显著;(2)进一步的结构方程模型分析表明:青少年与父母性话题沟通开放性对性行为具有显著的负向预测作用,对不赞同同伴性行为的态度具有显著的正向预测作用;而青少年与父母性话题沟通舒适感对不赞同同伴性行为的态度具有显著的负向预测作用;(3)依恋对性话题沟通和青少年的性行为的关系有显著的调节作用,与完全安全依恋的家庭相比,在与父母依恋都不安全的家庭中,青少年与父母性话题沟通的开放性对青少年的性行为有更强的预测力 相似文献
864.
865.
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. 相似文献
866.
调查娱乐场所服务女性的性行为特征及其安全套使用情况,为预防性病/艾滋病健康教育和政策制定提供参考信息。采用立意抽样方法对我省南昌和萍乡两地娱乐场所服务女性进行问卷调查。娱乐场所服务女性卖淫比例较高,卖淫者安全套使用比例和频率不高,且卖淫者安全套使用存在不平衡现象。必须进一步加大宣传教育力度及强化干预工作。 相似文献
867.
Brown AM Deacon BJ Abramowitz JS Dammann J Whiteside SP 《Behaviour research and therapy》2007,45(4):819-828
Cognitive-behavioral therapy (CBT) and pharmacotherapy are the most well-established treatments for childhood anxiety disorders. This study examined how parents (N=71) seeking treatment for their child's anxiety disorder perceive the acceptability, believability, and effectiveness of these treatments. While both treatments were perceived favorably, CBT was rated as more acceptable, believable, and effective in the short- and long-term. Children's treatment history influenced parents' perceptions of pharmacotherapy, with parents of children with no treatment history perceiving medication treatment as less acceptable and believable than parents of children with a history of medication alone or in combination with behavior therapy. No effect of treatment history was found for perceptions of CBT. Significant positive correlations emerged between parents' perceived acceptance and believability for pharmacotherapy and child age and level of dysfunction due to their child's anxiety, respectively. The level of the child's anxiety was not significantly correlated with parents' perceptions of either CBT or pharmacotherapy. Our results suggest that parents of anxious children prefer CBT to medication for the treatment of their child's anxiety disorder. Directions for future research are discussed. 相似文献
868.
We evaluated the effects of a behavioral treatment on the safe passing of sharp instruments using the hands-free technique among hospital operating room personnel during surgical procedures. Treatment consisted of participative goal setting, task clarification, and feedback. The average percentage of sharp instruments passed safely increased from 32% to 64% and 31% to 70% between baseline and treatment phases in the inpatient and outpatient surgery units, respectively. Five-month follow-up data suggested maintenance of treatment effects. These findings suggest the utility of organizational behavior management strategies in reducing risky behavior in hospital settings. 相似文献
869.
Berg WK Wacker DP Cigrand K Merkle S Wade J Henry K Wang YC 《Journal of applied behavior analysis》2007,40(3):545-552
The results of a functional analysis of problem behavior and a paired-choice assessment were compared to determine whether the same social reinforcers were identified for problem behavior and an appropriate response (time allocation). The two assessments were conducted in classroom settings with 4 adolescents with mental retardation who engaged in severe problem behavior. Each student's classroom teacher served as the therapist for all phases of assessment. The two assessment procedures identified the same social reinforcers for problem and appropriate behavior for 3 of 4 participants. 相似文献
870.
Factors that influence choice between qualitatively different reinforcers (e.g., a food item or a break from work) are important to consider when arranging treatments for problem behavior. Previous findings indicate that children who engage in problem behavior maintained by escape from demands may choose a food item over the functional reinforcer during treatment (DeLeon, Neidert, Anders, & Rodriguez-Catter, 2001; Lalli et al., 1999). However, a number of variables may influence choice between concurrently available forms of reinforcement. An analogue for treatment situations in which positive reinforcement for compliance is in direct competition with negative reinforcement for problem behavior was used in the current study to evaluate several variables that may influence choice. Participants were 5 children who had been diagnosed with developmental disabilities and who engaged in problem behavior maintained by escape from demands. In the first phase, the effects of task preference and schedule of reinforcement on choice between a 30-s break and a high-preference food item were evaluated. The food item was preferred over the break, regardless of the preference level of the task or the reinforcement schedule, for all but 1 participant. In the second phase, the quality of the break was manipulated by combining escape with toys, attention, or both. Only 1 participant showed preference for the enriched break. In the third phase, choice of a medium- or low-preference food item versus the enriched break was evaluated. Three of 4 participants showed preference for the break over the less preferred food item. Results extend previous research by identifying some of the conditions under which individuals who engage in escape-maintained behavior will prefer a food reinforcer over the functional one. 相似文献