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51.
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ABSTRACT

By using the probabilistic framework of production efficiency, the paper develops time-dependent conditional efficiency estimators performing a non-parametric frontier analysis. Specifically, by applying both full and quantile (robust) time-dependent conditional estimators, it models the dynamic effect of health expenditure on countries’ technological change and technological catch-up levels. The results from the application reveal that the effect of per capita health expenditure on countries’ technological change and technological catch-up is nonlinear and is subject to countries’ specific income levels.  相似文献   
53.
In this paper, we investigate the k-nearest neighbours (kNN) estimation of nonparametric regression model for strong mixing functional time series data. More precisely, we establish the uniform almost complete convergence rate of the kNN estimator under some mild conditions. Furthermore, a simulation study and an empirical application to the real data analysis of sea surface temperature (SST) are carried out to illustrate the finite sample performances and the usefulness of the kNN approach.  相似文献   
54.
《Risk analysis》2018,38(9):1820-1829
Ethical analysis is often needed in the preparation of policy decisions on risk. A three‐step method is proposed for performing an ethical risk analysis (eRA). In the first step, the people concerned are identified and categorized in terms of the distinct but compatible roles of being risk‐exposed, a beneficiary, or a decisionmaker. In the second step, a more detailed classification of roles and role combinations is performed, and ethically problematic role combinations are identified. In the third step, further ethical deliberation takes place, with an emphasis on individual risk‐benefit weighing, distributional analysis, rights analysis, and power analysis. Ethical issues pertaining to subsidiary risk roles, such as those of experts and journalists, are also treated in this phase. An eRA should supplement, not replace, a traditional risk analysis that puts emphasis on the probabilities and severities of undesirable events but does not cover ethical issues such as agency, interpersonal relationships, and justice.  相似文献   
55.
针对21世纪对英语口语思辨表达能力的要求,分析了英语口语和思辨性表达的关系,回顾了提升英语口语思辨能力的理论文献,总结了在英语听说课程中实践话题性内容听力导入、小组活动、演讲范例分析和呈现、文学经典作品导入和呈现有效提升英语口语思辨表达能力的作用。  相似文献   
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Political support is a multidimensional construct encompassing evaluations of political leaders and institutions (specific support) as well as adherence to basic regime principles (diffuse support). Scholars have traditionally assumed that diffuse and specific support are driven by different forces and evolve largely independently. Prior empirical work, however, has struggled to untangle the two support dimensions and focused predominantly on cross-national differences, ignoring their dynamics. This paper develops an analytical and empirical approach to examine the levels and dynamic interplay of both support dimensions and estimate their determinants, applying it to South American democracies between 1996 and 2015. Contrary to received wisdom, we show that both dimensions are quite volatile and closely linked in this region. In particular, negative economic shocks not only undermine support for government actors, but also fuel democratic disenchantment. Nonetheless, while regime support is rather fickle in South America, it can be ultimately resistant to performance fluctuations.  相似文献   
58.
ABSTRACT

Violations of linearity, symmetry, and equidistance of scale points in semantic differential scales may be due to respondents failing to figure out antonyms, to a positivity bias, or to respondents curtailing their reading the options. Multiple correspondence analysis on data provided by a randomized between-subjects experiment (split-ballot), using a web survey of 537 German residents, shows that bipolar semantic differential scales allow for linear measurement and conceal no positivity bias, and that using not suitable adjective pairs in semantic differential scales destroys symmetry.  相似文献   
59.
《Risk analysis》2018,38(8):1634-1655
The work in the article presents the development of an application guide based on feedback and comments stemming from various railway actors on their practices of SIL allocation to railway safety‐related functions. The initial generic methodology for SIL allocation has been updated to be applied to railway rolling stock safety‐related functions in order to solve the SIL concept application issues. Various actors dealing with railway SIL allocation problems are the intended target of the methodology; its principles will be summarized in this article with a focus on modifications and precisions made in order to establish a practical guide for railway safety authorities. The methodology is based on the flowchart formalism used in CSM (common safety method) European regulation. It starts with the use of quantitative safety requirements, particularly tolerable hazard rates (THR). THR apportioning rules are applied. On the one hand, the rules are related to classical logical combinations of safety‐related functions preventing hazard occurrence. On the other hand, to take into account technical conditions (last safety weak link, functional dependencies, technological complexity, etc.), specific rules implicitly used in existing practices are defined for readjusting some THR values. SIL allocation process based on apportioned and validated THR values is finally illustrated through the example of “emergency brake” subsystems. Some specific SIL allocation rules are also defined and illustrated.  相似文献   
60.
在数据包络分析中,大量的交叉效率模型已被提出。然而选择不同的目标模型将实现不一样的交叉效率评价。本文基于针对单个决策单元实施的对抗型和仁慈型两个交叉效率模型,用合作博弈方法来研究交叉效率模型的选取,并利用Shapley值对决策单元进行排序。最后通过实例分析显示该排序方法充分利用了最小交叉效率和最大交叉效率的信息完全排序了所有决策单元,具有一定的综合性和合理性。  相似文献   
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