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1.
In this work, we assume that the sequence recording whether or not an ozone exceedance of an environmental threshold has occurred in a given day is ruled by a non-homogeneous Markov chain of order one. In order to account for the possible presence of cycles in the empirical transition probabilities, a parametric form incorporating seasonal components is considered. Results show that even though some covariates (namely, relative humidity and temperature) are not included explicitly in the model, their influence is captured in the behavior of the transition probabilities. Parameters are estimated using the Bayesian point of view via Markov chain Monte Carlo algorithms. The model is applied to ozone data obtained from the monitoring network of Mexico City, Mexico. An analysis of how the methodology could be used as an aid in the decision-making is also given.  相似文献   
2.
This paper proposes a probabilistic frontier regression model for binary type output data in a production process setup. We consider one of the two categories of outputs as ‘selected’ category and the reduction in probability of falling in this category is attributed to the reduction in technical efficiency (TE) of the decision-making unit. An efficiency measure is proposed to determine the deviations of individual units from the probabilistic frontier. Simulation results show that the average estimated TE component is close to its true value. An application of the proposed method to the data related to the Indian public sector banking system is provided where the output variable is the indicator of level of non-performing assets. Individual TE is obtained for each of the banks under consideration. Among the public sector banks, Andhra bank is found to be the most efficient, whereas the United Bank of India is the least.  相似文献   
3.
国际政治的参与情境决定行动者的博弈行为类型,参与情境变迁将导致行动者行为发生变化。能源安全是国家对外政策的核心议题之一。1973年爆发的第一次石油危机,凸显了能源安全问题的重要性,改变了二战后国际能源政治的参与情境,构建了行动者新的博弈类型,调整了国际能源政治行动者的博弈策略。为了有效应对国际能源政治的情境变迁,美国通过协调与其他国家的能源关系,设置能源安全国际议程,最终确定了新的国际能源秩序。当前,我国在积极参与国际能源合作的过程中,第一次石油危机后国际能源政治的情境变迁以及国际社会的应对策略具有十分重要的启示意义。  相似文献   
4.
Assessment of analytical similarity of tier 1 quality attributes is based on a set of hypotheses that tests the mean difference of reference and test products against a margin adjusted for standard deviation of the reference product. Thus, proper assessment of the biosimilarity hypothesis requires statistical tests that account for the uncertainty associated with the estimations of the mean differences and the standard deviation of the reference product. Recently, a linear reformulation of the biosimilarity hypothesis has been proposed, which facilitates development and implementation of statistical tests. These statistical tests account for the uncertainty in the estimation process of all the unknown parameters. In this paper, we survey methods for constructing confidence intervals for testing the linearized reformulation of the biosimilarity hypothesis and also compare the performance of the methods. We discuss test procedures using confidence intervals to make possible comparison among recently developed methods as well as other previously developed methods that have not been applied for demonstrating analytical similarity. A computer simulation study was conducted to compare the performance of the methods based on the ability to maintain the test size and power, as well as computational complexity. We demonstrate the methods using two example applications. At the end, we make recommendations concerning the use of the methods.  相似文献   
5.
根据支撑基础、责任负担、保障水平以及民众需求等维度,可以把民生保障划分为托底型、基本型、改善型以及富裕型等四种类型。改善型民生是经济社会发展到一定阶段的产物,也是国家治理体系与治理能力现代化的客观要求。它是指通过各类民生项目的安排及民生待遇优化以促进民众生活得到持续改善、社会发展水平得到提升的一种制度类型,是民生项目更加齐全、内容更为完善、治理水平更高、使民众各按其分的民生模式,是人们的日常生活与服务消费支出总额持续增长以便能够提升生活水平的民生类型,是那种不断满足人的需要特别是较高层次需要的模式类型,也是更有助于形成社会结构稳定、国家长治久安的民生制度类型,因而具有综合性、完善性、激励性以及发展性等特点。这要求我们优化民生类型设计及民生投入结构,补齐改善型民生短板,营造良好社会秩序,扎实推进国家治理体系及治理能力现代化建设。  相似文献   
6.
ABSTRACT

Risks of exclusion can occur in multiple forms and start early in life. Early school leavers are especially at risk of social exclusion as this is strongly related to turbulent school-to-work-transitions. These young people often find themselves in low-qualified work or unemployment. In this article, we explore the labour market experiences of early school leavers in Flanders, Belgium. In total, 15 in-depth interviews were conducted with nine early school leavers and analysed following a grounded theory approach. Our results demonstrate the difficulties early school leavers encounter in their transitions from school to work and their precarious situation in the labour market. Of particular relevance are the insights gained in revealing the perspectives of young people on the importance of educational qualifications, work experience and participation in the labour market, as well as the strategies they develop to enter the labour market without educational qualifications.  相似文献   
7.
8.
Despite the evidence of effectiveness of positive parenting programs, little is known about the typology of changes that parents at psychosocial risk undergo after an intervention. We compared individual patterns of change in three parenting outcomes in 256 at risk parents with young children attending the group‐based Growing Up Happily in the Family program delivered in municipal social services. We identified four clusters of individual change: Cluster 1 (30.6%) had negative changes in parental child‐rearing attitudes and parenting stress, Cluster 2 (27.7%) had positive changes in child‐rearing attitudes and negative results in parental perceived competence, and Cluster 3 (24.1%) and Cluster 4 (17.6%) showed overall better results. Residential area, type of social support, and quality of implementation characterized cluster membership. Participants in clusters with better results were more satisfied with the program than those with worse results. Practical recommendations are provided for the successful implementation of group parenting programs in family preservation services.  相似文献   
9.
An important source of neighborhood change occurs when there is a turnover in the housing unit due to residential mobility and the new residents differ from the prior residents based on socio-demographic characteristics (what we term social distance). Nonetheless, research has typically not asked which characteristics explain transitions with higher social distance based on a number of demographic dimensions. We explore this question using American Housing Survey data from 1985 to 2007, and focus on instances in which the prior household moved out and is replaced by a new household. We focus on four key characteristics for explaining this social distance: the type of housing unit, the age of the housing unit, the length of residence of the exiting household, and the crime and social disorder in the neighborhood. We find that transitions in the oldest housing units and for the longest tenured residents result in the greatest amount of social distance between new and prior residents, implying that these transitions are particularly important for fostering neighborhood socio-demographic change. The results imply micro-mechanisms at the household level that might help explain net change at the neighborhood level.  相似文献   
10.
随着城镇化进程不断加快,城镇功能和城市文明向农村地区的扩散已成为一种必然。对于传统农业地区,城镇化的关键在于立足自身资源禀赋,对城镇化的路径和推进机制做出切合实际的选择。在这方面,山东省平阴县孝直镇借助新型农村社区建设和农业现代化推进新型城镇化的模式为研究分析此类问题提供了一个可资借鉴的案例。  相似文献   
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