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991.
Pigeons show a preference for an alternative that provides them with discriminative stimuli (sometimes a stimulus that predicts reinforcement and at other times a stimulus that predicts the absence of reinforcement) over an alternative that provides them with nondiscriminative stimuli, even if the nondiscriminative stimulus alternative is associated with 2.5 times as much reinforcement (Stagner & Zentall, 2010). In Experiment 1 we found that the delay to reinforcement associated with the nondiscriminative stimuli could be reduced by almost one half before the pigeons were indifferent between the two alternatives. In Experiment 2 we tested the hypothesis that the preference for the discriminative stimulus alternative resulted from the fact that, like humans, the pigeons were attracted by the stimulus that consistently predicted reinforcement (the Allais paradox). When the probability of reinforcement associated with the discriminative stimulus that predicted reinforcement was reduced from 100% to 80% the pigeons still showed a strong preference for the discriminative stimulus alternative. Thus, under these conditions, the Allais paradox cannot account for the sub-optimal choice behavior shown by pigeons. Instead we propose that sub-optimal choice results from positive contrast between the low expectation of reinforcement associated with the discriminative stimulus alternative and the much higher obtained reinforcement when the stimulus associated with reinforcement appears. We propose that similar processes can account for sub-optimal gambling behavior by humans.  相似文献   
992.
The purpose of this study was to develop an accurate metabolic equation for estimating steady-state oxygen consumption (VO2) during submaximal NuStep exercise. Adults (N = 40; M age = 64.0 yr., SD = 6.5; M height = 170.1 cm, SD = 9.1; M weight = 85.7 kg, SD = 19.9) performed two randomized testing sessions. Each session consisted of six stages with combinations of four workloads (1, 3, 5, and 7) at 3 cadences (60, 80, and 100 steps/min.). Multiple regression analysis to predict steady-state VO2 from NuStep workload (W), NuStep steps/min., and subject body mass resulted in the following model (R2 = .73): Steady-state VO2 = 3.5 + 0.016 (W* steps/min.) + 0.092 (steps/min.) - 0.053 (weight). The standard error of the estimate and total error for the prediction of steady-state VO2 under all NuStep workload conditions were 2.3 mL/kg/min. and 2.4 mL/kg/ min., respectively. The standard error of the estimate and total error values are similar to those previously reported in the literature regarding the accuracy of metabolic equations for other exercise modalities. These findings support the use of the equation developed to predict steady-state VO2 for NuStep exercise in older adult clientele.  相似文献   
993.
Health and well-being (H&W) improve during vacation. However, it is unclear whether this general development applies to all employees, while also little is known about the underlying processes causing such an improvement. Our research questions were: (1) Does every worker experience a positive effect of vacation on H&W? and (2) Can vacation activities and experiences explain changes in H&W during vacation? In a 7-week longitudinal field study, 96 workers reported their H&W 2 weeks before, during, 1 week, 2 and 4 weeks after a winter sports vacation on 6 indicators (health status, mood, fatigue, tension, energy level and satisfaction). Sixty percent of the sample experienced substantial improvement of H&W during and after vacation. Yet, a small group experienced no (23%) or a negative effect of vacation (17%). Spending limited time on passive activities, pleasure derived from vacation activities, and the absence of negative incidents during vacation explained 38% of the variance in the vacation effect. Although vacation has a positive, longer lasting effect for many, it is not invariably positive for all employees. Choosing especially pleasant vacation activities and avoiding negative incidents as well as passive activities during active vacations apparently contributes to the positive effect of vacation on H&W.  相似文献   
994.
Two experiments are reported that investigate the impact of misinformation on memory accuracy and metacognitive resolution. In Experiment 1, participants viewed a series of photographs depicting a crime scene, were exposed to misinformation that contradicted details in the slides, and later took a recognition memory test. For each answer, participants were required to indicate whether they were willing to testify (report) their answer to the Court and to rate confidence. Misinformation impaired memory accuracy but it had no effect on resolution, regardless of whether resolution was indexed with confidence‐rating measures (γ correlation and mean confidence) or a report‐option measure (type‐2 discrimination: d′). In Experiment 2, a similar accuracy‐confidence dissociation was found, and the misinformation effect occurred mostly with fine‐grained responses, suggesting that responding was based on recollected details. We argue that the results support source‐monitoring (SM) accounts of accuracy and resolution rather than accounts based on trace strength. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
995.

Purpose  

Despite the potential for researcher decisions to negatively impact the reliability of meta-analysis, very few methodological studies have examined this possibility. The present study compared three independent and concurrent telecommuting meta-analyses in order to determine how researcher decisions affected the process and findings of these studies.  相似文献   
996.
This article describes the development of the Therapist Use-of-Self Orientation Questionnaire (TUSO-Q), an instrument designed to measure therapists’ use-of-self orientations while working with clients. A total of 373 therapists participated in this study. Exploratory factor analysis in the structural equation modeling context revealed three different therapist use-of-self orientations: Transpersonal, Contextual, and Instrumental. The final model provided an excellent fit to the data. TUSO-Q scores exhibited satisfactory evidence of internal consistency reliability and construct validity. Implications for the scale’s use in clinical research and training are discussed.  相似文献   
997.
The present study examined the role of neuroticism and extraversion in the effects of written emotional disclosure in patients diagnosed with gynaecological cancer. It was hypothesized that high levels of neuroticism would be associated with an increase in distress after emotional disclosure as mediated by heightened negative affect and avoidance post-disclosure. Conversely, we expected high extraversion to be associated with decreased distress as mediated by heightened positive moods and a decrease in avoidance. Eighty-eight participants were randomly assigned to participate in an expressive writing task versus a control writing task. Distress and avoidance were assessed at baseline and 6 months post-writing. Negative and positive mood were assessed immediately following writing. Multiple regression confirmed that neuroticism but not extraversion moderates the effects of emotional disclosure on distress, however no significant mediating relationships were found.  相似文献   
998.
Predictions of fuzzy-trace theory and neurobiological approaches are examined regarding risk taking in a classic decision-making task--the framing task--as well as in the context of real-life risk taking. We report the 1st study of framing effects in adolescents versus adults, varying risk and reward, and relate choices to individual differences, sexual behavior, and behavioral intentions. As predicted by fuzzy-trace theory, adolescents modulated risk taking according to risk and reward. Adults showed standard framing, reflecting greater emphasis on gist-based (qualitative) reasoning, but adolescents displayed reverse framing when potential gains for risk taking were high, reflecting greater emphasis on verbatim-based (quantitative) reasoning. Reverse framing signals a different way of thinking compared with standard framing (reverse framing also differs from simply choosing the risky option). Measures of verbatim- and gist-based reasoning about risk, sensation seeking, behavioral activation, and inhibition were used to extract dimensions of risk proneness: Sensation seeking increased and then decreased, whereas inhibition increased from early adolescence to young adulthood, predicted by neurobiological theories. Two additional dimensions, verbatim- and gist-based reasoning about risk, loaded separately and predicted unique variance in risk taking. Importantly, framing responses predicted real-life risk taking. Reasoning was the most consistent predictor of real-life risk taking: (a) Intentions to have sex, sexual behavior, and number of partners decreased when gist-based reasoning was triggered by retrieval cues in questions about perceived risk, whereas (b) intentions to have sex and number of partners increased when verbatim-based reasoning was triggered by different retrieval cues in questions about perceived risk.  相似文献   
999.
This study examined whether widely accepted suicide risk factors are useful in predicting suicide-related hospitalization, beyond history of a suicide attempt, in high-risk treatment-seeking veterans with depression and substance dependence. Negative mood regulation expectancies were the only significant predictor of hospitalization during 6-months of outpatient treatment. History of a suicide attempt was the only significant predictor of hospitalization during the one-year follow-up period. Results suggest that within high-risk populations, standard suicide risk factors may not identify individuals who will engage in suicidal behaviors resulting in hospitalization. Assessing negative mood regulation expectations may assist in identifying those most at risk.  相似文献   
1000.
We uncover new insights on the role of virtuality on team information sharing. A new two-dimensional conceptualization of information sharing (Mesmer-Magnus & DeChurch, 2009) enabled us to reconcile past inconsistencies in the virtual team literature. Recasting the findings of 94 studies (total number of groups = 5596; total N approximately = 19,702) into this framework reveals three key insights. First, virtuality improves the sharing of unique information, but hinders the openness of information sharing. Second, unique information sharing is more important to the performance of face-to-face teams than is open information sharing, whereas open information sharing is more important to the performance of virtual teams than is unique information sharing. Third, the effects of virtuality on information sharing are more curvilinear than linear – such that low levels of virtuality improve information sharing, but high levels hider it. Implications for research and practice are discussed.  相似文献   
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