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21.
Genetic counseling for women of advanced maternal age who are considering prenatal testing continues to be based on a principle of nondirectiveness. We interviewed 11 genetic counseling students and four counselors about how they experience and manage, in practice, the tensions between the ideology of nondirectiveness and the acknowledged reality that one can never be truly nondirective. We found that our respondents creatively resolve this tension—simultaneously resisting and adhering to the values of nondirectiveness and information-giving—in individual and situation-specific ways. This resolution is facilitated by the extent to which information given to counselees is fluid, mobile and context-dependent, but these very features of information also have critical implications for both the norms and the practice of genetic counseling.  相似文献   
22.
A Bayesian approach for simultaneous optimization of test-based decisions is presented using the example of a selection decision for a treatment followed by a mastery decision. A distinction is made between weak and strong rules where, as opposed to strong rules, weak rules use prior test scores as collateral data. Conditions for monotonicity of optimal weak and strong rules are presented. It is shown that under mild conditions on the test score distributions and utility functions, weak rules are always compensatory by nature. The authors are indebted to Wilbert Kallenberg for his valuable comments and to Jan Gulmans for providing the data for the empirical example. The names of the authors are alphabetical; they are equally responsible for the contents of this paper.  相似文献   
23.
Frederick Ferré 《Zygon》1996,31(1):93-99
Abstract. My comment on Ethics in an Age of Technology, volume 2 of Ian G. Barbour's Gifford Lectures, acknowledges the excellence of Barbour's depictions of the social-cum-technological problems facing humanity in the coming millennium. Barbour's proposed solutions, too, are reasonable—but usually presuppose fundamental reforms in social values, especially within the powerful industrialized societies. Without further analysis of technology and values, this seems to make such solutions “impossible dreams.” My thesis is that clear analysis of the ideal aspects of technology (as itself the embodiment of knowledge and values), plus clues from Alfred North Whitehead on the dynamics of social change, can reinforce hope even in “impossible” dreams. First, technology, though embodied in solid material machinery and powerful social institutions, is no more “solid” than constant reaffirmation of the values behind it (as was the case with the Berlin Wall). Second, great ideals, over time, have the power to help create the conditions of their own possibility. Social change is both “pushed” by coercive forces (e.g., climate changes) and “pulled” by great values (e.g., human dignity). Therefore there are practical benefits to be gained from attending to, and celebrating, even currently “impossible” dreams as they work to make themselves possible.  相似文献   
24.
Ruth Marcus 《Psychometrika》1978,43(1):133-139
A general method of devising stepwise multiple testing procedures with fixed experimentwise error is applied to the problem of non-parametric randomized block design with ordered alternatives. In addition, the method is applied to other models with ordered alternatives.The author wishes to thank the referees for helpful suggestions.  相似文献   
25.
Huynh Huynh 《Psychometrika》1978,43(3):317-325
Cohen's kappa index is reformulated for multiple classifications based on exchangeable random variables. It is found that kappa is between 0 and 1 inclusive. Two characterizations for kappa are stated in terms of the relationship between such random variables. Within the normal test score model, kappa increases with test reliability and test length. Furthermore, when based on binary classifications, kappa is an inverse U-shaped function of the cutoff score. These trends also hold for the beta-binomial test score model.Paper read at the Spring meeting of the Psychometric Society, Bell Laboratories (Murray Hill, New Jersey), March 1976.The editorial assistance and helpful comments of Leonard S. Feldt, Sarah P. Seaman-Huynh, and the three referees are gratefully acknowledged.  相似文献   
26.
The Comprehensive Ability Battery (CAB) was used to assess 18 primary mental abilities in 53 white, male prison inmates for whom highly reliable ratings of psychopathy were available. None of the correlations between ratings of psychopathy and scores on the CAB tests was significant, and the overall pattern or structure of abilities was the same for inmates with low and high ratings of psychopathy. The possibility is raised that the personality characteristics of psychopaths make them appear to be brighter and more creative than they actually are. Compared with norms for male high school students, the inmates as a group generally performed well, falling near the 50th percentile on 11 of the tests. The inmates performed significantly better than the normative sample on tests of verbal ability, esthetic judgment, aiming, and representational drawing, and significantly worse on tests of ideational fluency, spontaneous flexibility, and word fluency.This research was supported by Grant MT-4511 from the Medical Research Council of Canada.  相似文献   
27.
Level of school education and performance on an intelligence test were analysed for 32 557 Danish young adult males as a function of the geographical region in which they were reared. Positive associations were found between both educational levels and test scores on the one hand, and the proportion of infants attending kindergartens in the given regions (according to official statistics) on the other. Adults who were reared in regions where kindergarten attendance had been high tended to have higher educational levels and test scores, although the data do not permit a precise estimate of the magnitude of this effect. The relationship between kindergarten attendance and intelligence test score appears to have been mediated by educational level. Kindergarten attendance was more common in regions with high population density and high average incomes but the relationship of kindergarten attendance to educational level was significantly independent of these associations. These findings are consistent with the hypothesis that kindergarten attendance can have long-term educational benefits, and might therefore partially explain the upward trend in intelligence test scores over the last few decades.  相似文献   
28.
Huynh Huynh 《Psychometrika》1977,42(4):601-608
Two simple classes of mastery scores which are suitable for hand calculations are presented for beta-binomial test score distributions combined with linear and cubic referral success. The models provide a simple way to explore the consequences of selecting an arbitrary mastery score. Such assessment would be useful whenever the test user is not willing to posta priori a loss ratio, but wishes to look at the various consequences before aiming at a particular score.  相似文献   
29.
The effect of candy reward on I.Q. scores was investigated in 72 first- and second-grade children. All subjects were administered Form A of the Peabody Picture Vocabulary Test and, based upon these scores, were divided into three blocks: low, middle, and high. From each block, subjects were randomly assigned to one of three conditions (contingent reward, noncontingent reward, or no reward) that were in effect during administration of Form B. Results showed that candy given contingent upon each correct response increased I.Q. scores for the initially low scoring subjects, but had no influence on the scores of middle and high scoring subjects.  相似文献   
30.
Computerized classification testing (CCT) aims to classify persons into one of two or more possible categories to make decisions such as mastery/non-mastery or meet most/meet all/exceed. A defining feature of CCT is its stopping criterion: the test terminates when there is enough confidence to make a decision. There is abundant research on CCT with a single cut-off, and two common stopping criteria are the sequential probability ratio test (SPRT) statistic and the generalized likelihood ratio statistic (GLR). However, there is a relative scarcity of research extending the SPRT to the multi-hypothesis case for when there is more than one cut-off. In this paper, we propose a new multi-category GLR (mGLR) statistic as well as a stochastically curtailed version of the CCT with three or more categories. A simulation study was conducted to show that the mGLR statistic outperformed the existing stopping rules by generating shorter average test length without sacrificing classification accuracy. Results also revealed that the stochastically curtailed mGLR successfully increased test efficiency in certain testing conditions.  相似文献   
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