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71.
A multidisciplinary group of genetic and other professionals discuss a complex case of familial conflict over access to genetic information. One twin wishes to know the results of her deceased mother's tests for BRCA1 mutations; a second twin objects to researchers making this information available. As the case discussion unfolds, the apparent facts of this case are called into question and the lines of ethical certainty become less clear. 相似文献
72.
The cloning of BRCA1, a susceptibility gene for inherited breast cancer, has made genetic screening possible for individuals and families whose medical histories are suggestive of an inherited predisposition to breast cancer. To date, few systematic attempts have been made to determine the level of knowledge about breast cancer genetics among women who are likely to seek BRCA1 screening when it becomes widely available. The present study attempted to assess the general knowledge about BRCA1 mutations in two groups: (1) first-degree relatives (FDRs) of breast cancer patients; and (2) women with a previous diagnosis of breast cancer. A self-administered, thirty-item questionnaire was developed through a pilot study. Ten of the items were objective, factual questions about breast cancer genetics. Responses to these questions were used to generate an overall knowledge score for each respondent. The study population was moderately knowledgeable about breast cancer genetics, with an average score of 5.35 out of 10. Counselors should not underestimate the importance of evaluating each counselee's existing knowledge about breast cancer, which can affect the provision and reception of genetic information. In particular, specific areas of knowledge that may be confusing or misunderstood were identified and these topics are discussed in detail. 相似文献
73.
KATRI RÄIKKÖNEN PERTTI KESKIVAARA LIISA KELTIKANGAS-JÄRVINEN EVA BÜTZOW HEIKKI LYYTINEN 《Scandinavian journal of psychology》1995,36(2):142-152
The association between psychophysiological responses (heart rate, skin conductance and blood volume) and Type A behavior was studied in adolescent boys (n = 48) in computer-controlled experiments. Although psychophysiological arousal was related to the type of stress-evoking element, task-specificity did not result in significant psychophysiological differences between Type As and Nontype As. The indication is that physiological arousal may be a constitutional characteristic of Type A behavior. The multidimensionality of type A behavior must be considered in any investigation examining the psychophysiological Type A-Nontype A differences. Different Type A dimensions, together with previously found psychological differences, were related to specific psychophysiological reactions. 相似文献
74.
JAN SMEDSLUND 《Scandinavian journal of psychology》1994,35(1):1-15
Five studies published in the Journal of Experimental Social Psychology and selected without advance knowledge of their contents, were analyzed with respect to the epistemic and modal status of their hypotheses. It was found that the general hypotheses were a priori and noncontingent (necessarily true), whereas the local auxiliary hypotheses were empirical and contingent. Hence, the data were only relevant for the latter. It is conjectured that such pseudoempirical studies may abound in contemporary psychology. They remain undiscovered because researchers unreflectively believe that all propositions that can be related to data are empirical and that psychological terms need not be defined. Only when terms are defined and presuppositions (axioms) are stated, can one determine the epistemic and modal status of a given proposition, and, hence, whether or not a study is pseudoempirical. 相似文献
75.
Game logic and its applications I 总被引:3,自引:0,他引:3
This paper provides a logic framework for investigations of game theoretical problems. We adopt an infinitary extension of classical predicate logic as the base logic of the framework. The reason for an infinitary extension is to express the common knowledge concept explicitly. Depending upon the choice of axioms on the knowledge operators, there is a hierarchy of logics. The limit case is an infinitary predicate extension of modal propositional logic KD4, and is of special interest in applications. In Part I, we develop the basic framework, and show some applications: an epistemic axiomatization of Nash equilibrium and formal undecidability on the playability of a game. To show the formal undecidability, we use a term existence theorem, which will be proved in Part II.The authors thank Hiroakira Ono for helpful discussions and encouragements from the early stage of this research project, and Philippe Mongin, Mitio Takano and a referee of this journal for comments on earlier versions of this paper. The first and second authors are partially supported, respectively, by Tokyo Center of Economic Research and Grant-in-Aids for Scientific Research 04640215, Ministry of Education, Science and Culture.Presented by H. Ono 相似文献
76.
Harald Wohlrapp 《Argumentation》1998,12(3):341-350
77.
Willem A. Wagenaar Gideon B. Keren 《Organizational behavior and human decision processes》1985,36(3):406-416
The question addressed in this study is whether experts are better calibrated than lay people. We investigated how well people are calibrated when they assess the probabilities of card combinations in the game of blackjack. Three groups of subjects were used: professional dealers, statistical experts, and control subjects. The results showed that experience and statistical expertise do not make people better calibrated in this task. It is argued that the concept of calibration is not wholly appropriate to describe the obtained deviations from the normatively correct responses. This is illustrated by a discriminant analysis performed on the signed deviation scores, which resulted in an almost perfect separation of the three groups, although they were overlapping with respect to calibration. 相似文献
78.
Sara M. Freedman James S. Phillips 《Organizational behavior and human decision processes》1985,35(3):397-416
Situational performance constraints, task interest, and pay contingencies were manipulated in a laboratory study in order to investigate the cognitive mechanisms associated with the previously observed detrimental effects of constraints on affective task reactions. It was hypothesized that feelings of task competence and self-determination would account for both the direct and the interactive effects of constraints on motivation and satisfaction. The results of the study indicated that despite the fact that participants' performance was being constrained and they were aware of these constraints, the mere presence of the constraints alone failed to result in lower levels of satisfaction or motivation on a proofreading task. Post hoc analyses suggested that the constraints, in fact, led to negative affective task reactions when they also reduced participants' feelings of competence and self-determination. Interestingly, participants' generalized locus of control was associated with such effects. Internals tended to maintain stronger feelings of competence and self-determination than externals in the presence of constraints, thereby also maintaining greater motivation and satisfaction. 相似文献
79.
Paul M. Kohn Helen M. Annis Hau Lei David W. Chan 《Personality and individual differences》1985,6(6):753-763
This paper tests a meta-model of youthful marijuana use on students in Grades 11, 12 and 13. Although the specific models for each grade varied in detail, all followed a meta-model making the following assumptions: (1) that use or nonuse of marijuana depends primarily on attitude towards use; (2) that attitude largely reflects the perceived functional and dysfunctional consequences of use; and (3) that what people perceive as functional or dysfunctional depends on relevant personality characteristics. All three models showed satisfactory goodness-of-fit in terms of nonsignificant overidentification tests (minimum P > 0.25) and small discrepancies between observed correlations and the corresponding theoretically implied correlations. A notable feature of the Grade 13 data in contrast to those for Grade 12 and previously reported findings was the seeming unimportance of the perceived value of marijuana use for gaining acceptance from peers. It was suggested that this might reflect the selective survival into Grade 13 in the sampled community of more independently-oriented students. 相似文献
80.
Lane has argued that kantowitz and Knight incorrectly predicted an interaction between primary and secondary task difficulty for the variable-allocation model of attention. It is shown that such an interaction is indeed obtained if task-performance difficulty is defined in terms of capacity and only reasonable transformations of data are permitted. This interaction holds for any set of monotonic resource operating characteristics. 相似文献