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851.
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   
852.
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   
853.
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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A conceptual framework is presented in which mental load and stress are regarded as two distinct biobehavioural states in the work environment that differ in energy mobilization, mood and coping strategy. The framework combines two types of theory that are based on human performance research using laboratory tasks on the one hand and applied research in the work environment on the other. A high workload is regarded as an important but not a critical factor in the development of stress symptoms. Even under unfavourable conditions it is possible to work intensively and to be highly activated without feelings of strain or psychosomatic complaints. In contrast, working conditions that provide few possibilities for control and little social support or are associated with reduced well-being and increased health risks. The two states differ in activation, coping style and mood. A proper distinction is important not only for theory building but also for the reconstruction of the work environment. It may lead to recommendations that aim to enhance the work efficiency of employees while reducing the probability that stress responses will occur.  相似文献   
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Abstract Three explanations typically are offered for differences in earnings: (1) individuals have different levels of human capital and hold different jobs (endowments differ), (2) rewards to human capital and job characteristics differ (returns differ), and (3) some combination of differences in endowments and returns explain variations in earnings. We argue that the structure of labor markets in nonmetropolitan (nonmetro) areas differs from that in metropolitan (metro) areas such that returns, as well as endowments, vary. These variations in returns favor metropolitan workers, explaining the predominant portion of the metro/nonmetro earnings gap. We examine the earnings differences for metro and nonmetro men and women in both 1977 and 1987, showing that returns outweigh endowments in explaining that gap for both men and women, although their importance decreases over the ten-year period. Research to improve our understanding of how differences in labor market structure produce differential returns has begun and may yield yet another avenue for action for policymakers interested in reducing metro/nonmetro inequalities.  相似文献   
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Estimation of Common Cause Failure Rates Based on Uncertain Event Data   总被引:2,自引:0,他引:2  
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