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991.
The success of the Global Polio Eradication Initiative promises to bring large benefits, including sustained improvements in quality of life (i.e., cases of paralytic disease and deaths avoided) and costs saved from cessation of vaccination. Obtaining and maintaining these benefits requires that policymakers manage the transition from the current massive use of oral poliovirus vaccine (OPV) to a world without OPV and free of the risks of potential future reintroductions of live polioviruses. This article describes the analytical journey that began in 2001 with a retrospective case study on polio risk management and led to development of dynamic integrated risk, economic, and decision analysis tools to inform global policies for managing the risks of polio. This analytical journey has provided several key insights and lessons learned that will be useful to future analysts involved in similar complex decision-making processes.  相似文献   
992.
993.
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   
994.
995.
This study analyses the effectiveness of the European Community's Environmental Assessment Directive of 1985 in its application in the U.K. forestry sector. It assesses the applicability of the regulations in the provision of the public and private outputs of forestry. The environmental assessment regulation may contribute to the provision of the optimal amount of these public and private goods in theory, but it is concluded that, in common with initial results of the environmental assessment process in other sectors, the regulations do not make this contribution in practice in the forestry sector. The main deficiencies of the environmental statements examined were the failure to identify the significant potential impacts; to present alternative project sites and design features; and the erroneous measure of particular externalities. The environmental assessment process was also found to be unsatisfactory in the lack of public accessibility and consultation. The need for revision of the process in the forestry sector is highlighted.  相似文献   
996.
This paper first describes a program AGREE calculating many variants of coefficients for interobserver agreement. A pilot program MOCK was written, aimed at helping unitiated users of AGREE to select the most appropriate coeflcient, given the data type and the research goal. It is a mock-up version of the data entrance and analysis sections of AGREE, to which are added some menus and a knowledge-based CONSULTANT system questioning the user. Results of a small experiment with four variants of the CONSULTANT are presented. This leads to a discussion of desirable features for this kind of help programs and preprocessors for specialized statistical software.  相似文献   
997.
998.
The author shows how to find M‐estimators of location whose generating function is monotone and which are optimal or close to optimal. It is easy to identify a consistent sequence of estimators in this class. In addition, it contains simple and efficient approximations in cases where the likelihood function is difficult to obtain. In some neighbourhoods of the normal distribution, the loss of efficiency due to the approximation is quite small. Optimal monotone M‐estimators can also be determined in cases when the underlying distribution is known only up to a certain neighbourhood. The author considers the e‐contamination model and an extension thereof that allows the distributions to be arbitrary outside compact intervals. His results also have implications for distributions with monotone score functions. The author illustrates his methodology using Student and stable distributions.  相似文献   
999.
Sometimes, in industrial quality control experiments and destructive stress testing, only values smaller than all previous ones are observed. Here we consider nonparametric quantile estimation, both the ‘sample quantile function’ and kernel-type estimators, from such record-breaking data. For a single record-breaking sample, consistent estimation is not possible except in the extreme tails of the distribution. Hence replication is required, and for m. such independent record-breaking samples the quantile estimators are shown to be strongly consistent and asymptotically normal as m-→∞. Also, for small m, the mean-squared errors, biases and smoothing parameters (for the smoothed estimators) are investigated through computer simulations.  相似文献   
1000.
《孔雀东南飞》是一出家庭悲剧 ,但在中国封建社会的土壤中产生的这一悲剧在全世界却具有普遍性。在老年寡妇和她的儿子、儿媳所组成的非完整的扩大家庭中 ,婆婆和儿媳争夺她们共同关心的男子的情感 ,是这个家庭内的永恒难题。家庭内的情感争夺与社会制度和民族传统并无必然联系。  相似文献   
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