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81.
1989-2001年阿根廷的"新自由主义"改革历程,证明了经济与政治的不均衡发展是导致发展中国家陷入现代化困境的重要因素之一;经济现代化具有天然的不均衡性,国家必须实现政治发展,以政治上的均衡手段,即通过提供更加完整、更加充盈、公正的均衡性公共物品,消除或减轻经济现代化 的不均衡后果,引导经济现代化的正确发展方向.  相似文献   
82.
袭警案件的多发凸显了警察人权面临的困境。警察人权处于警察与国家、警察与公民双重关系之中,结合行政法学上“特别权力关系”和“反射利益”两个基本概念研究警察的多重身份和警察权对警察人权的影响,有利于在理论和实践上对警察权益保护的研究能在一个更广阔的平台上进行。  相似文献   
83.
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   
84.
The authors examined whether nonresident fathers provide informal support to their children and whether support stops if their ex‐partner goes on to have a child with a new man. A logistic regression analysis of longitudinal survey and administrative data for 434 women who received welfare in Wisconsin showed that fathers are less likely to provide informal support when their ex‐partner has a child with a new partner. Alternative models that control for unobserved characteristics suggest somewhat different results, providing stronger evidence of declines in support that can be shared across family members than in support that can be directed to a particular child.  相似文献   
85.
The development of one's sexual minority identity is often stunted by a heterosexist society. For individuals with multiple minority oppressions, this process becomes even more complicated. As such, there has been a call among researchers for more empirical research on the experiences of lesbian, gay, bisexual (LGB) individuals from racial/ethnic minority groups. This study uses qualitative methods to fill gaps in the literature related to identity development among same-gender attracted Middle Eastern/Arab individuals living in the United States. From 12 interviews, 13 themes associated with intersectionality, race/ethnicity, sexual identity development, discrimination, stigma, oppression, and invisibility. Themes, subthemes, and their implications are discussed.  相似文献   
86.
研究零售商质量控制和供应链成员风险规避背景下供应链网络均衡问题。应用条件风险值度量风险规避程度,利用变分不等式理论描绘供应链参与者的最优经济行为,设计供应链网络均衡模型,考虑风险规避和质量控制策略对均衡的影响,证明均衡解存在且唯一,并运用Levenberg-Marquardt算法求解均衡模型。最后对重要参数进行数值分析,揭示质量控制和风险规避对供应链均衡解以及参与者条件风险值的影响。研究表明:供应链参与者越规避风险越有利于产品质量水平的提高,风险规避程度的加深会降低制造商或零售商自身的CVaR,同时增大对方的CVaR,对因产品合格率提高带来的利益而言,制造商所得优于零售商。  相似文献   
87.
本文假定透明交易者对额外投资机会回报率的标准差(方差,投资风险)存在暧昧,这种认知暧昧性抑制了透明交易者的投资行为,会导致风险资产溢价过高及社会福利损失.透明交易者是暧昧厌恶的投资者,其投资决策依据光滑暧昧厌恶模型,需求函数呈现连续且光滑的特征.而不透明交易者,通过支付一定的信息获取成本获得私有信息而具有信息优势,他们是标准的风险厌恶的投资者.通过构建理性预期均衡,本文的研究发现:初始资产严格为正的透明交易者将获得严格为正的超额收益;提高信息获取成本将减少不透明交易者的比例,从而增加风险资产溢价,降低福利水平,因而不是一项好的管制措施;而旨在提高市场透明度降低交易者暧昧性的举措总有利于提高福利水平.  相似文献   
88.
For ethical reasons, group sequential trials were introduced to allow trials to stop early in the event of extreme results. Endpoints in such trials are usually mortality or irreversible morbidity. For a given endpoint, the norm is to use a single test statistic and to use that same statistic for each analysis. This approach is risky because the test statistic has to be specified before the study is unblinded, and there is loss in power if the assumptions that ensure optimality for each analysis are not met. To minimize the risk of moderate to substantial loss in power due to a suboptimal choice of a statistic, a robust method was developed for nonsequential trials. The concept is analogous to diversification of financial investments to minimize risk. The method is based on combining P values from multiple test statistics for formal inference while controlling the type I error rate at its designated value.This article evaluates the performance of 2 P value combining methods for group sequential trials. The emphasis is on time to event trials although results from less complex trials are also included. The gain or loss in power with the combination method relative to a single statistic is asymmetric in its favor. Depending on the power of each individual test, the combination method can give more power than any single test or give power that is closer to the test with the most power. The versatility of the method is that it can combine P values from different test statistics for analysis at different times. The robustness of results suggests that inference from group sequential trials can be strengthened with the use of combined tests.  相似文献   
89.
Multiphase experiments are introduced and an overview of their design and analysis as it is currently practised is given via an account of their development since 1955 and a literature survey. Methods that are available for designing and analysing them are outlined, with an emphasis on making explicit the role of the model in their design. The availability of software and its use is described in detail. Overall, while multiphase designs have been applied in areas such as plant breeding, plant pathology, greenhouse experimentation, product storage, gene expression studies, and sensory evaluation, their deployment has been limited.  相似文献   
90.
In clinical trials, missing data commonly arise through nonadherence to the randomized treatment or to study procedure. For trials in which recurrent event endpoints are of interests, conventional analyses using the proportional intensity model or the count model assume that the data are missing at random, which cannot be tested using the observed data alone. Thus, sensitivity analyses are recommended. We implement the control‐based multiple imputation as sensitivity analyses for the recurrent event data. We model the recurrent event using a piecewise exponential proportional intensity model with frailty and sample the parameters from the posterior distribution. We impute the number of events after dropped out and correct the variance estimation using a bootstrap procedure. We apply the method to an application of sitagliptin study.  相似文献   
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