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To develop a survey, the Bioethical Issues in Biostatistical Consulting Questionnaire, for investigating bioethical issues in analysis, a comprehensive literature review was conducted to specify areas of bioethics. Through a focus group study and the evaluation by 10 biostatisticians, the questionnaire was constructed. Validation must involve a panel of experts. Now, test-retest reliability and factor analysis should be conducted on a group of eligible subjects. 相似文献
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The occurrence, time course, and repeatability of response rate increases following the onset of extinction, the extinction burst, were studied in three experiments. Nine pigeons were exposed to at least 5 cycles of 5-session blocks of conditioning followed by 8-session blocks of extinction. In different experiments, conditioning sessions either were a fixed-ratio (FR) or variable-ratio (VR) schedule, and transitions from the last conditioning session in each cycle to the first extinction session were conducted between or within sessions. A single response rate increase occurred when overall response rates were considered. Restricting analyses to the first minute of extinction sessions sometimes revealed increases in response rates, although this finding was inconsistent. The frequency and magnitude of these increases differed across exposures to extinction both across and within pigeons. Additionally, how responding during extinction was measured (i.e., the level of analysis) influenced whether increases above baseline levels were observed. These results suggest that the extinction burst may be influenced by the manner of transition to extinction and the way in which early extinction responding is measured. Under the best conditions, the extinction burst does not appear to be a ubiquitous effect of extinction. 相似文献
475.
Sexual compliance involves willing acquiescence to unwanted sex for the good of the relationship. Northeastern U.S. undergraduate women in exclusive relationships (N?=?193) anonymously reported on their sexual behaviors and motives, investment in ideal womanhood, and romantic well-being. About 37% (n?=?72) reported sexual compliance. As expected, sexually compliant women reported greater investment in ideal womanhood than non-compliant women, although unexpectedly, they reported less overall satisfaction and similar commitment. Women’s compliance was motivated more by pursuing relationship enhancement than by avoiding conflict. Regardless, only avoidance motives were associated (negatively) with relationship satisfaction. Compliant women who reported more frequent compliance motivated by conflict avoidance reported particularly low satisfaction. These findings challenge conceptualizations of women’s sexual compliance as beneficial. 相似文献
476.
R. J. Katz 《Aggressive behavior》1978,4(2):153-172
A variety of strategies have been employed in assessing the role of catecholamines (CA) in predatory behavior; the results of these various approaches are reviewed. While it remains difficult to ascribe a single biologically significant role to CA at this time, this may at least in part reflect measurement considerations, problems in the widely varying experimental models, pharmacologic side effects, and failures to categorically distinguish the differing contributions of individual CA systems in the control of predation. The potential role of such factors in determining the outcome of an experiment are reviewed and possible functional contributions of CA systems are suggested. 相似文献
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The generalization hypothesis of abstract-concept learning was tested with a meta-analysis of rhesus monkeys (Macaca mulatta), capuchin monkeys (Cebus apella), and pigeons (Columba livia) learning a same/different (S/D) task with expanding training sets. The generalization hypothesis states that as the number of training items increases, generalization from the training pairs will increase and could explain the subjects' accurate novel-stimulus transfer. By contrast, concept learning is learning the relationship between each pair of items; with more training items subjects learn more exemplars of the rule and transfer better. Having to learn the stimulus pairs (the generalization hypothesis) would require more training as the set size increases, whereas learning the concept might require less training because subjects would be learning an abstract rule. The results strongly support concept or rule learning despite severely relaxing the generalization-hypothesis parameters. Thus, generalization was not a factor in the transfer from these experiments, adding to the evidence that these subjects were learning the S/D abstract concept. 相似文献
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