BAYESIAN HYPER‐LASSOS WITH NON‐CONVEX PENALIZATION

The Lasso has sparked interest in the use of penalization of the log‐likelihood for variable selection, as well as for shrinkage. We are particularly interested in the more‐variables‐than‐observations case of characteristic importance for modern data. The Bayesian interpretation of the Lasso as the maximum a posteriori estimate of the regression coefficients, which have been given independent, double exponential prior distributions, is adopted. Generalizing this prior provides a family of hyper‐Lasso penalty functions, which includes the quasi‐Cauchy distribution of Johnstone and Silverman as a special case. The properties of this approach, including the oracle property, are explored, and an EM algorithm for inference in regression problems is described. The posterior is multi‐modal, and we suggest a strategy of using a set of perfectly fitting random starting values to explore modes in different regions of the parameter space. Simulations show that our procedure provides significant improvements on a range of established procedures, and we provide an example from chemometrics.     

Television Viewing by School-Age Children: Associations with Physical Activity,Snack Food Consumption and Unhealthy Weight

Alarm about the increasing prevalence of childhood obesity has focussed attention on individual lifestyle behaviours that may contribute to unhealthy weight. Television viewing is often a focus of the obesity debate. Not only is it sedentary, it also has the potential to influence other lifestyle behaviours either by displacing physical activities or through the consumption of high energy snack foods while watching TV. The research reported here uses data from 2,143 Australian 6–7 year children to examine the lifestyle behaviours associated with excess weight. These children spent 90 min each day watching television, 100 min each day in physical activity, and 39% consumed high levels of snack foods. Nearly one in five (18%) were overweight or obese. After adjustment for family and child characteristics, more time spent watching television was associated with more snacking and less physical activity. However, television viewing was associated with children’s weight status, but snacking and physical activities were not. These findings confirm the existence from a young age, of a cluster of lifestyle behaviours that are associated with unhealthy weight status.     

Wilson Confidence Intervals for the Two-Sample Log-Odds-Ratio in Stratified 2 × 2 Contingency Tables

Large-sample Wilson-type confidence intervals (CIs) are derived for a parameter of interest in many clinical trials situations: the log-odds-ratio, in a two-sample experiment comparing binomial success proportions, say between cases and controls. The methods cover several scenarios: (i) results embedded in a single 2 × 2 contingency table; (ii) a series of K 2 × 2 tables with common parameter; or (iii) K tables, where the parameter may change across tables under the influence of a covariate. The calculations of the Wilson CI require only simple numerical assistance, and for example are easily carried out using Excel. The main competitor, the exact CI, has two disadvantages: It requires burdensome search algorithms for the multi-table case and results in strong over-coverage associated with long confidence intervals. All the application cases are illustrated through a well-known example. A simulation study then investigates how the Wilson CI performs among several competing methods. The Wilson interval is shortest, except for very large odds ratios, while maintaining coverage similar to Wald-type intervals. An alternative to the Wald CI is the Agresti-Coull CI, calculated from the Wilson and Wald CIs, which has same length as the Wald CI but improved coverage.     

差序式领导与员工亲组织非伦理行为：圈内人和圈外人视角

 亲组织非伦理行为是近年来国内外组织管理学界日益关注的重要问题。已有研究表明，领导对员工亲组织非伦理行为的形成有重要影响。但相关研究成果多来自西方学界，基于中国文化情景的研究成果还十分有限，而聚焦于极具华人社会文化特色和内涵的本土领导对员工亲组织非伦理行为的影响研究更是匮乏，有待进一步拓展。        基于社会交换理论、社会认同理论和社会认知理论，从圈内人和圈外人视角出发，探讨中国组织文化情景下差序式领导对员工亲组织非伦理行为的影响以及领导组织代表性和员工集体主义倾向的调节作用。通过分阶段调研的方式，收集14家长三角地区本土企业457套调研数据，采用验证性因子分析、层次回归分析和Bootstrap法进行实证检验。        研究结果表明，差序式领导对圈内人和圈外人亲组织非伦理行为存在正向影响，但影响程度不存在显著差异；领导组织代表性正向调节差序式领导对圈内人和圈外人亲组织非伦理行为的影响，相较于圈内人，高领导组织代表性对差序式领导与圈外人亲组织非伦理行为之间关系的调节作用更强；员工集体主义倾向正向调节差序式领导对圈内人和圈外人亲组织非伦理行为的影响，但调节程度不存在显著差异。        实证检验中国组织文化情景下差序式领导对员工亲组织非伦理行为的影响机制，丰富了领导对员工亲组织非伦理行为的影响研究，是对本土组织管理研究的有益补充；从圈内人和圈外人两条路径分析员工亲组织非伦理行为的形成机制，为深入理解圈内人和圈外人的认知过程及差异提供了经验证据，并对已有研究视角进行有益整合；提出并验证了领导组织代表性和员工集体主义倾向的调节作用，补充了员工亲组织非伦理行为产生的边界条件。     

On Past and Future of Community: A Pragmatic Analysis

Charles Sanders Peirce proposed a semiotic that directed attention to the person or people who are providing interpretation, making place for the social and cultural. Following Peirce, we consider the meanings and consequences the term “community” has in an international context. We argue that English affords a richer set of meanings to community, which was not paralleled in the languages of Southeast Asia. The encounter between English and Southeast Asian languages has lexical consequences, but more momentous are the cultural changes they index. In Southeast Asian cultures, there is less need for “community” to take on broader meanings, since those cultures assume social relationality. Thus, the spread of English “community” could be associated with a rise of individualism in these other cultures, but it could also impoverish the Anglophone West, which would be denied alternative frameworks in which associational and affective meanings of community are unnecessary.     

Medically necessary?

Coverage decisions can ultimately be traced back to three words in the original health policy contract: medically necessary and investigational. Investigational as a coverage exclusion applies to the minority of cases, in which there is inadequate data to validate the effectiveness of the intervention. In contrast, the majority of coverage decisions are based on medical necessity. Over the years the concept of medical necessity has evolved to encompass a multitude of medical management strategies. This discussion highlights the variable uses of the concept of medical necessity in terms of: (1) Determining the most appropriate intensity of service and place of service; (2) determining whether the proposed therapy is medically appropriate for the patient's condition; (3) distinguishing between medically necessary services and those that are performance enhancing or discretionary in nature; (4) making a distinction between medically necessary, cosmetic, and reconstructive services; and (5) defining medical necessity in accordance with generally accepted principles of good medical practice.     

Youth mobilisations and political generations: young activists in political change movements during and since the twentieth century

This paper uses political generations theory to examine the main youth mobilisations during and since the twentieth century: pre-1939 fascist and communist movements; the student movements of the 1960s and 70s; movements that challenged colonial and neo-colonial rulers in less developed countries and young people's involvement in the revolutions that saw the end of communism in East-Central and South-East Europe in 1989. Conclusions from this review of the past are used in considering the likely significance of subsequent outbursts of political activism among young people: the ‘colour revolutions’ and other instances of youth mobilisation in former Soviet republics and other ex-communist countries; the Arab Spring and the series of movements that have challenged neo-liberalism – Anti-Globalisation, the Indignados and the Occupy movements. The paper notes that youth mobilisations that have led to the formation of new political generations that have changed their countries' politics then transformed the countries have typically extended over several decades, that initially youthful leaders have sometimes been middle-aged or older before achieving political power and that many of their actions on achieving power have been at variance with their youthful ideals. In conclusion, it is argued that it is still too early to tell whether any of the recent youth mobilisations signal the formation of new political generations.     

A‐Way Express Courier

This article examines the social return on investment (SROI) of A‐Way Express Courier for the major stakeholder group of the organization, its employees. Specifically, it explores the mental health, employment, and standard of living outcomes that A‐Way provides for the employees who are consumer/survivors of the mental health system. Overall, the impacts of the organization contributed significantly to improvements in the health and quality of life of the employees. They also translate into economic benefits for the employees and the community. Because of A‐Way's roots in the consumer/survivor movement of the 1970s, the article suggests that positive psychology could be a valuable framework with which to explain A‐Way's impact.