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11.
Proportional hazards are a common assumption when designing confirmatory clinical trials in oncology. This assumption not only affects the analysis part but also the sample size calculation. The presence of delayed effects causes a change in the hazard ratio while the trial is ongoing since at the beginning we do not observe any difference between treatment arms, and after some unknown time point, the differences between treatment arms will start to appear. Hence, the proportional hazards assumption no longer holds, and both sample size calculation and analysis methods to be used should be reconsidered. The weighted log‐rank test allows a weighting for early, middle, and late differences through the Fleming and Harrington class of weights and is proven to be more efficient when the proportional hazards assumption does not hold. The Fleming and Harrington class of weights, along with the estimated delay, can be incorporated into the sample size calculation in order to maintain the desired power once the treatment arm differences start to appear. In this article, we explore the impact of delayed effects in group sequential and adaptive group sequential designs and make an empirical evaluation in terms of power and type‐I error rate of the of the weighted log‐rank test in a simulated scenario with fixed values of the Fleming and Harrington class of weights. We also give some practical recommendations regarding which methodology should be used in the presence of delayed effects depending on certain characteristics of the trial.  相似文献   
12.
Public Organization Review -  相似文献   
13.
税法中不确定概念下的理论空间以及税务行政的实践需求共同营造了税务行政裁量的制度空间,而不规范的税务行政裁量则为不规范的税收执法提供了操作机会。通过对税法文本中不确定概念理论缘由的寻求,以及税收征管中实践动因的梳理,税务行政裁量权的规范化确有必要性。为达成税法运行各司其职中的彼此制衡,有必要强化比例性原则在税务行政裁量中的运用,以此限制税权介入纳税人私域的范围与限度,并提供明确化的宏观指引;利用行政裁量基准“行政自制”与“规则之治”的双重品质,借助标准化的文本修正,为规范化的税收执法预设行为轨迹、构建外在制约并压缩裁量空间;以纳税人的同意权为基础,设计符合税法特殊性的程序规则,形成立体化的纳税人救济路径。最终形成税务行政裁量权积极运作与规范运行的制度环境。  相似文献   
14.
Journal of Nonverbal Behavior - Past research has demonstrated that children understand distinct emotion concepts and can accurately recognize facial expressions of distinct emotions by a young...  相似文献   
15.
曾国藩在传统文化和家庭氛围影响下形成了浓厚的乡土情结,贯穿曾国藩一生的乡土情结为其事业和交友产生了深刻的影响。在京为官时期对同乡以及家乡的特别关注,折射出曾国藩浓浓的乡土情结。曾国藩在乡土情结的影响下创建了湘军,为其幕府的建立储备了人才,在乡土情结的感召下与同乡建立了深厚友谊,成就了一生的事业。  相似文献   
16.
A growing body of research demonstrates that believing action to reduce the risks of climate change is both possible (self‐efficacy) and effective (response efficacy) is essential to motivate and sustain risk mitigation efforts. Despite this potentially critical role of efficacy beliefs, measures and their use vary wildly in climate change risk perception and communication research, making it hard to compare and learn from efficacy studies. To address this problem and advance our understanding of efficacy beliefs, this article makes three contributions. First, we present a theoretically motivated approach to measuring climate change mitigation efficacy, in light of diverse proposed, perceived, and previously researched strategies. Second, we test this in two national survey samples (Amazon's Mechanical Turk N = 405, GfK Knowledge Panel N = 1,820), demonstrating largely coherent beliefs by level of action and discrimination between types of efficacy. Four additive efficacy scales emerge: personal self‐efficacy, personal response efficacy, government and collective self‐efficacy, and government and collective response efficacy. Third, we employ the resulting efficacy scales in mediation models to test how well efficacy beliefs predict climate change policy support, controlling for specific knowledge, risk perceptions, and ideology, and allowing for mediation by concern. Concern fully mediates the relatively strong effects of perceived risk on policy support, but only partly mediates efficacy beliefs. Stronger government and collective response efficacy beliefs and personal self‐efficacy beliefs are both directly and indirectly associated with greater support for reducing the risks of climate change, even after controlling for ideology and causal beliefs about climate change.  相似文献   
17.
This paper develops a unified model of dual and unitary job holding based on a Stone-Geary utility function. The model incorporates both constrained and unconstrained labor supply. Panel data methods are adapted to accommodate unobserved heterogeneity and multinomial selection into six mutually exclusive labor supply regimes. We estimate the wage and income elasticities arising from selection and unobserved heterogeneity as well as from the Stone-Geary Slutsky equations. The labor supply model is estimated with data from the British Household Panel Survey 1991–2008. Among dual job holders, our study finds that the Stone-Geary income and wage elasticities are much larger for labor supply to the second job compared with the main job. When the effects of selection and unobserved heterogeneity are taken account of, the magnitudes of these elasticities on the second job tend to be significantly reduced.  相似文献   
18.
This article contributes to understanding transformational change towards gender equality by examining the transformational change potential of a mentoring programme for women, a type of gender equality intervention both criticized and praised for its ability to bring about change. Drawing upon an empirical case study of a mentoring programme for women academics in a Dutch university, we explore three dimensions of transformational change: organizational members (i) discussing and reflecting upon gendered organizational norms and work practices; (ii) creating new narratives; and (iii) experimenting with new work practices. Our findings indicate five specific conditions that enable transformational change: cross‐mentoring, questioning what is taken for granted, repeating participation and individual stories, facilitating peer support networks and addressing and equipping all participants as change agents. We suggest that these conditions should be taken into account when (re)designing effective organizational gender equality interventions.  相似文献   
19.
This research focuses upon employment in the new economy, exploring labour protection and social protection in the digital age in China. Through an empirical survey conducted in three Chinese cities, social insurance and the labour rights of employees in the digital economic sector, such as gig employment, e-commerce, and various other forms of online employment, have been examined in-depth. This study reveals new regulatory loopholes in the digital labour market, which have substantially eroded the basis of social policy arrangements in China, “softening” participation in social insurance branches and compliance with labour regulations remarkably. Drawing upon the theoretical concepts of Polanyi on embeddedness and disembeddedness, we argue that the digital employment sector in China has been increasingly disembedded from social institutions and social control. The new configuration in the digital field of social policy requires novel conceptual models and institutional settings to cope with increasing social risks in virtual spaces.  相似文献   
20.
中国的市场仍旧存在某种程度的分割,如何突破这种市场分割到异地拓展市场是企业要考虑的现实问题。以前的研究主要是从省级层面或国家层面进行宏观分析。文章创新地从政企关系视角入手来考察市场分割情形下微观层面的企业异地市场拓展,也是首先把市场分割(和异地市场)分为省内(本市外)市场、省外市场和海外市场三个不同层面来研究的论文。用世界银行的调查数据从微观企业个体层面检验了企业异地市场拓展的可能。实证研究结果发现,市场分割确实阻碍了企业异地市场拓展,但这仅限于省内市场而不是省外市场。此外,市场分割是有方向性的,从地方保护主义严重的市场里走出来的企业更容易拓展异地市场,但此结论仅适用于国内市场拓展而不适用于海外市场拓展。良好的政企关系是有利于企业异地市场拓展的,但仅限于省外市场,对省内市场以及海外市场是无效的。文章解释了其中的原因,并分析了对于企业实践的启示。  相似文献   
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