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971.
972.
Summary.  Consider a clinical trial in which participants are randomized to a single-dose treatment or a placebo control and assume that the adherence level is accurately recorded. If the treatment is effective, then good adherers in the treatment group should do better than poor ad- herers because they received more drug; the treatment group data follow a dose–response curve. But, good adherers to the placebo often do better than poor adherers, so the observed adherence–response in the treatment group cannot be completely attributed to the treatment. Efron and Feldman proposed an adjustment to the observed adherence–response in the treatment group by using the adherence–response in the control group. It relies on a percentile invariance assumption under which each participant's adherence percentile within their assigned treatment group does not depend on the assigned group (active drug or placebo). The Efron and Feldman approach is valid under percentile invariance, but not necessarily under departures from it. We propose an analysis based on a generalization of percentile invariance that allows adherence percentiles to be stochastically permuted across treatment groups, using a broad class of stochastic permutation models. We show that approximate maximum likelihood estimates of the underlying dose–response curve perform well when the stochastic permutation process is correctly specified and are quite robust to model misspecification.  相似文献   
973.
The case of ufology demonstrates that cultural packaging—a sort of once-removed indication of scientific authority—can be key in creating knowledge accepted as scientific. This adds a new dimension to the argument that scientific legitimacy is constructed, not just from scientific methodologies and institutional location, but also of language, culture, rhetoric, and symbols. Fringe researchers can make their cases for legitimacy using a variety of strategies—few of which involve actual research. Outside of the scientific community, scientific-sounding explanations and proclamations of expert statuses hold sway. Ambiguities about what constitutes science can be capitalized upon by groups like the UFO research community that assembles shards of legitimacy using science as a cultural template.  相似文献   
974.
This study examined the stability and coherence of African‐American children's social support networks. Participants included a total of 106 3‐ to 4‐year‐old children attending Head Start centers located in the southeast. Children completed a social network interview in two consecutive years at the Head Start centers. These interviews tapped multiple dimensions of the support network including social embeddedness, proportion of the network providing support, and perceived support. Analyses focused on both the rank‐order stability of children with respect to network characteristics as well as stability of network relationships (the same individuals included in the network at both time periods). Results indicated age‐related increases in network size for adult and child categories, network size across three support domains, proportion of support scores, and perceived support from adults. In addition to age‐related changes, analyses revealed considerable rank‐order stability with respect to structural network dimensions, but very little rank‐order stability in proportion of support and perceived support scores. In contrast, both structural and supportive components of the children's networks were shown to be coherent over a one‐year period when specific network member relationships were examined. Discussion highlights both continuities and discontinuities in young children's social networks, and how data obtained in this study contribute to theory building and the systematic examination of African‐American children's emerging social networks.  相似文献   
975.
1. Brief planned and crisis admissions to an inpatient psychiatric unit are presented as a component supportive of outpatient care and case management for chronically mentally ill patients. 2. Typical patients admitted to this inpatient short-term program are those experiencing a life stress or temporary crisis; chronically mentally ill patients who cycle and experience exacerbations of their illness; and those who need to make the transition from an acute inpatient unit to community living. 3. The Brief Admission Program treats the individual's response to and the consequences of a lifelong illness and enables the patient to return to his previous level of functioning and continue necessary outpatient treatment.  相似文献   
976.
Adaptive sampling without replacement of clusters   总被引:1,自引:0,他引:1  
In a common form of adaptive cluster sampling, an initial sample of units is selected by random sampling without replacement and, whenever the observed value of the unit is sufficiently high, its neighboring units are added to the sample, with the process of adding neighbors repeated if any of the added units are also high valued. In this way, an initial selection of a high-valued unit results in the addition of the entire network of surrounding high-valued units and some low-valued “edge” units where sampling stops. Repeat selections can occur when more than one initially selected unit is in the same network or when an edge unit is shared by more than one added network. Adaptive sampling without replacement of networks avoids some of this repeat selection by sequentially selecting initial sample units only from the part of the population not already in any selected network. The design proposed in this paper carries this step further by selecting initial units only from the population, exclusive of any previously selected networks or edge units.  相似文献   
977.
978.
979.
This study situates five top transnational policy–planning groups within the larger structure of corporate power that is constituted through interlocking directorates among the world's largest companies. Each group makes a distinct contribution towards transnational capitalist hegemony both by building consensus within the global corporate elite and by educating publics and states on the virtues of one or another variant of the neo–liberal paradigm. Analysis of corporate–policy interlocks reveals that a few dozen cosmopolitans – primarily men based in Europe and North America and actively engaged in corporate management – knit the network together via participation in transnational interlocking and/or multiple policy groups. As a structure underwriting transnational business activism, the network is highly centralized, yet from its core it extends unevenly to corporations and individuals positioned on its fringes. The policy groups pull the directorates of the world's major corporations together, and collaterally integrate the lifeworld of the global corporate elite, but they do so selectively, reproducing regional differences in participation. These findings support the claim that a well–integrated global corporate elite has formed, and that global policy groups have contributed to its formation. Whether this elite confirms the arrival of a transnational capitalist class is a matter partly of semantics and partly of substance.  相似文献   
980.
Supervision as further education of vice-headmasters Our offer of further education aims at an improvement of executive activities of viceheadmasters. With the help of their first experiences with our concept they’ll become acquainted with the various processes of change in schools and can use it as an opportunity to support them. That’s our contribution to the development of the executive personnel in the schools of Sachsen-Anhalt.  相似文献   
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