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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.
This article presents a review of 20 tests designed for assessing the academic English listening skill of second or foreign language learners. The available test information has been systematically condensed in purpose, listening construct, task characteristics, and validity evidence. It was found that most of the tests were developed for proficiency and placement purposes in academic contexts, with few of the tests serving for making workplace decisions. Also, global, local, and inferential skills constitute the construct in most listening comprehension tests. A practical approach for justifying the uses of these tests for different stakeholders is discussed. This review is a valuable resource for educators, administrators, test developers, and researchers looking for a comprehensive analysis of existing English tests that assess listening comprehension in second or foreign language learners.  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.
ABSTRACT

Scholarly textbooks often follow a logic where suitable empirical cases are selected to illustrate the theoretical and analytical points that we as scholars want to make. But what would happen if we would do the opposite: build a textbook on a novel written by a novelist for such purpose and let the theories explain the actions and emotions of fictional characters? In this article, we share and reflect upon our experiences of co-authoring a textbook in organization theory together with a professional novelist. We argue that the novel can function as an eye-opener in organizational analysis, forcing us to look beyond more static and rationalistic perspectives on organizations as well as the stereotypes of such. We build and relate our experiences to the growing literature about using fiction in scholarly work and discuss the potential of such genre-bending work when we bring in flesh and blood into the analyses.  相似文献   
16.
Population and Environment - Human activity is a major driver of change and has contributed to many of the challenges we face today. Detailed information about human population distribution is...  相似文献   
17.
There is considerable speculation that female political empowerment could improve population health. Yet, evidence to date is limited, and explanations for why political empowerment would matter and the conditions under which this might be enhanced or muted are not well understood. In this article, we draw on theoretical work on the politics of representation to frame an investigation of whether increases in the percentage of females in a country’s parliament influence mortality rates. We further examine whether the relationship is conditioned by extent of democracy and economic and social development. Through multivariate longitudinal regression, we analyze four indicators of mortality in 155 countries spanning 1990 to 2014 with controls for initial country conditions, time-stable structural predispositions to higher mortality, and a number of time-varying potential confounders. Results indicate that a high level of female representation—30 % or greater in our models—has large negative associations with mortality, that these are particularly strong in lesser developed and weak democratic contexts, that high female political representation effectively offsets liabilities associated with low development, and that the relationships are robust to various operationalizations of social development. In the end, our research provides a particularly thorough accounting of the relationship between female political representation and population health, particularly by specifying the conditions under which female representation is most salient. In doing so, the research suggests important links between issues of female empowerment, political context, and developmental trajectories of countries more generally.  相似文献   
18.
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   
19.
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   
20.
Economic theory establishes that pension privatization weakens the link between old and young and so reduces the incentive to invest in public education in an economy with lower return rate of capital than growth rate of wage. However, empirical studies of the link change are few. In this paper, we investigate the effects of pension privatization and the central government’s subsidy to individual accounts on public education spending in a three-period overlapping generation model. And then, we take contemporary pension reforms in a number of Chinese provinces as offering natural experiment conditions. Using a difference-in-difference framework and 282 municipal districts panel data over years 1998–2009, we test the pension-education theoretical link change. Both our theoretical and empirical results confirm that pension privatization is adversely associated with local public spending on education in China. Private pension subsidies, moreover, magnify this effect. Our study supports the theoretical assertion and selective empirical findings of a negative intergenerational effect of pension privatization.  相似文献   
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