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81.
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
82.
In this paper, we examine the termination of children's mental health services. Analyses were based on the 901 families in the Fort Bragg Evaluation Project who participated at Wave 1 and Wave 2 six months later. The project compared a full continuum of care provided at a demonstration site with traditional care at two comparison sites. The results showed that in most cases families and providers were partners in decisions to terminate treatment. About half of the clients self-terminated or were terminated solely at the discretion of the provider. Providers tended to play a more dominant role in terminating restrictive services; families played a more central role in terminating outpatient care. Regardless of initial psychopathology, children in single-headed households, whose parents were dissatisfied with services, did not expect their child to cooperate with treatment and did not expect treatment to help their child, were more likely to terminate care than others. While the Demonstration site had significantly fewer terminations, the sites did not differ with regard to the reasons for termination, who participated in termination decisions, or the factors that affected the likelihood to terminate care. Of most interest, mental health outcomes among children who had terminated all care did not vary by reasons for termination or by who participated in the termination decision. 相似文献
83.
Eugene Schlossberger 《Science and engineering ethics》1997,3(3):317-326
Projects importing technology to lesser developed nations may raise five important concerns: famine resulting from substitution of cash crops for subsistence crops, the use of products banned in the United States but permitted overseas, the use of products safe in the U.S. but unsafe under local conditions, ecological consequences of technological change, and cultural disruption caused by displacing traditional ways of life. Are engineers responsible for the foreseeable hunger, environmental degradation, cultural disruption, and illness that results from the project? Are engineers guilty of paternalism if they refuse to accept the project for that reason? Criteria are given to help engineers assess the extent of their responsibility when working in lesser developed nations. 相似文献
84.
Gerard J. P. Van Breukelen 《Psychometrika》1997,62(4):525-544
This paper discusses two forms of separability of item and person parameters in the context of response time (RT) models. The first is separate sufficiency: the existence of sufficient statistics for the item (person) parameters that do not depend on the person (item) parameters. The second is ranking independence: the likelihood of the item (person) ranking with respect to RTs does not depend on the person (item) parameters. For each form a theorem stating sufficient conditions, is proved. The two forms of separability are shown to include several (special cases of) models from psychometric and biometric literature. Ranking independence imposes no restrictions on the general distribution form, but on its parametrization. An estimation procedure based upon ranks and pseudolikelihood theory is discussed, as well as the relation of ranking independence to the concept of double monotonicity.I am indebted to Wim van der Linden for bringing Thissen's (1983) paper to my notice, and to Martijn Berger, Frans Tan, and the anonymous reviewers for their constructive comments on earlier drafts of this paper. 相似文献
85.
Yiu-Fai Yung 《Psychometrika》1997,62(3):297-330
In this paper, various types of finite mixtures of confirmatory factor-analysis models are proposed for handling data heterogeneity. Under the proposed mixture approach, observations are assumed to be drawn from mixtures of distinct confirmatory factor-analysis models. But each observation does not need to be identified to a particular model prior to model fitting. Several classes of mixture models are proposed. These models differ by their unique representations of data heterogeneity. Three different sampling schemes for these mixture models are distinguished. A mixed type of the these three sampling schemes is considered throughout this article. The proposed mixture approach reduces to regular multiple-group confirmatory factor-analysis under a restrictive sampling scheme, in which the structural equation model for each observation is assumed to be known. By assuming a mixture of multivariate normals for the data, maximum likelihood estimation using the EM (Expectation-Maximization) algorithm and the AS (Approximate-Scoring) method are developed, respectively. Some mixture models were fitted to a real data set for illustrating the application of the theory. Although the EM algorithm and the AS method gave similar sets of parameter estimates, the AS method was found computationally more efficient than the EM algorithm. Some comments on applying the mixture approach to structural equation modeling are made.Note: This paper is one of the Psychometric Society's 1995 Dissertation Award papers.—EditorThis article is based on the dissertation of the author. The author would like to thank Peter Bentler, who was the dissertation chair, for guidance and encouragement of this work. Eric Holman, Robert Jennrich, Bengt Muthén, and Thomas Wickens, who served as the committee members for the dissertation, had been very supportive and helpful. Michael Browne is appreciated for discussing some important points about the use of the approximate information in the dissertation. Thanks also go to an anonymous associate editor, whose comments were very useful for the revision of an earlier version of this article. 相似文献
86.
该文提出了计量测验效度的一种统一方法。首先,根据测量目标由测验编制者提出一组可能的线性拟合模型,拟合模型的集合称作“测量目标结构空间”。然后运用实证性因素分析对各个假设的拟合模型进行多方面的拟合良好性检验。若其中的某一假设模型能最优地拟合预测资料,则该模型中的公共因素的方差总贡献与观测变量的总方差的比就可定义为该测验的效度 相似文献
87.
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89.
Matteo Selvini 《Contemporary Family Therapy》1997,19(3):315-335
The author examines the position of a child from whom important matters in his or her own life or key events in the family have been kept secret, outlines criteria by which the decision whether or not to unveil the secret should be made, and urges colleagues to gather more data and examine further family secrets. 相似文献
90.
Roni Berger 《Contemporary Family Therapy》1997,19(3):361-370
Immigration and remarriage are two stressful events that impact on family's functioning and well being. This article examines the effects on families of experiencing both of these transitions simultaneously. A case illustration is presented and implications for practice and for future research are discussed. The article is based on the clinical experience of the writer as well as on her study of stepfamilies from diverse cultural backgrounds. 相似文献