小费制：导游薪金制度创新研究

导游小费制已经成为国际惯例,因为它与旅游服务质量密切联系。我国国内受其影响,由明文禁收小费到旅游企业试行小费激励机制,变革已经发生,但仍然作为隐性存在,且很不规范。应正确认识小费制的合理性、可行性和优越性,使其尽早正常化和规范化,从而为我国旅游事业旅游业健康发展服务。     

Modeling Interdependent Risks

In an interdependent world the risks faced by any one agent depend not only on its choices but also on those of all others. Expectations about others' choices will influence investments in risk management and the outcome can be suboptimal for everyone. We model this as the Nash equilibrium of a game and give conditions for such a suboptimal equilibrium to be tipped to an optimal one. We also characterize the smallest coalition to tip an equilibrium, the minimum critical coalition, and show that this is also the cheapest critical coalition, so that there is no less expensive way to move the system from the suboptimal to the optimal equilibrium. We illustrate these results by reference to airline security and the control of infectious diseases via vaccination.     

Commentary on Knowledge Creation and Dissemination in Operations and Supply‐Chain Management

The title of this paper might have been Knowledge Creation and Dissemination in the POM Domain . Instead, these accomplished authors (who shall be dubbed with honorable intentions as RSST) define the POM domain as Operations and Supply‐Chain Management. Thereby, they leave no doubt that the POM domain spans the entire supply chain from shovels in the mine and seeds in the ground to recycled waste that is remanufactured and sold as new (as well as refurbished) products. RSST declare that sustainability of the ecosystem cycle must be achieved (even in the face of disaster conditions) by all institutions. RSST believe that practitioners can be taught the necessary attitudes and skills by business and engineering schools. It is noteworthy that the ecosystem cycle they describe is accompanied by marketing and financial decision cycles running parallel from inception of ideas to the “end of life” closure that starts a new cycle for closed‐loop product planning. For these coexisting, interdependent, all‐encompassing systems, the RSST team leaves no doubt about the evolution of teaching and research opportunities for young POM scholars. These authors focus on the fact that everything that is not morphing is likely to become counterproductive in the not too far future. This is a critical point of view which is based on the fact that the status quo is highly vulnerable. Also, very special is the RSST warning that changes are required in the status quo which must be made without damaging the existing fabric. This non‐disruptive way of doing POM business has been remarkably successful for the cohesion of the field over the past 25 years. There is agreement that it is great to shake things up without tearing those things apart. All of this leads to the conclusion that the advice of these authors (RSST) is correct and valuable. Debate and disputation of these points is encouraged and expected by the RSST team.     

全媒体环境下“引爆点”理论在主流新闻报道中的应用

全媒体时代的主流新闻发布面临着自媒体和社交媒体等无把关信息传播的越来越大的挑战,信息过量和注意力碎片化的媒介社会,重要信息往往会被垃圾化、泡沫化的消息所瞬间淹没。新闻媒体从新闻报道的策划到发布、传播都需要科学合理的把控,找到自身吸引公众关注的独特价值,制造“引爆点”,正确引导舆论。引爆点理论归纳出的流行三原则来阐发流行潮兴起的原因。引爆点理论中引发关注、引导潮流的思路对新闻报道也有一定的借鉴意义。     

Tip Work: Examining the Relational Dynamics of Tipping beyond the Service Counter

Tips constitute a growing form of income for roughly three million American workers today. While existing scholarship on tipping focuses on worker‐customer dynamics, it neglects the implications of gratuities beyond the service counter. Drawing on the case of restaurant workers in Los Angeles, this study analyzes tip work, the bundle of social relations and labor experiences framed by tips in commercial settings. I argue that tipping strains relations between subgroups of workers who, despite collectively producing service, are subject to unequal access to tip earnings. Tips thereby shape relations among workers in ways that exacerbate existing organizational and social hierarchies.     

Coping with missing data in phase III pivotal registration trials: Tolvaptan in subjects with kidney disease,a case study

Missing data cause challenging issues, particularly in phase III registration trials, as highlighted by the European Medicines Agency (EMA) and the US National Research Council. We explore, as a case study, how the issues from missing data were tackled in a double‐blind phase III trial in subjects with autosomal dominant polycystic kidney disease. A total of 1445 subjects were randomized in a 2:1 ratio to receive active treatment (tolvaptan), or placebo. The primary outcome, the rate of change in total kidney volume, favored tolvaptan (P < .0001). The key secondary efficacy endpoints of clinical progression of disease and rate of decline in kidney function also favored tolvaptan. However, as highlighted by Food and Drug Administration and EMA, the interpretation of results was hampered by a high number of unevenly distributed dropouts, particularly early dropouts. In this paper, we outline the analyses undertaken to address the issue of missing data thoroughly. “Tipping point analyses” were performed to explore how extreme and detrimental outcomes among subjects with missing data must be to overturn the positive treatment effect attained in those subjects who had complete data. Nonparametric rank‐based analyses were also performed accounting for missing data. In conclusion, straightforward and transparent analyses directly taking into account missing data convincingly support the robustness of the preplanned analyses on the primary and secondary endpoints. Tolvaptan was confirmed to be effective in slowing total kidney volume growth, which is considered an efficacy endpoint by EMA, and in lessening the decline in renal function in patients with autosomal dominant polycystic kidney disease.     

Sensitivity to censored‐at‐random assumption in the analysis of time‐to‐event endpoints

Over the past years, significant progress has been made in developing statistically rigorous methods to implement clinically interpretable sensitivity analyses for assumptions about the missingness mechanism in clinical trials for continuous and (to a lesser extent) for binary or categorical endpoints. Studies with time‐to‐event outcomes have received much less attention. However, such studies can be similarly challenged with respect to the robustness and integrity of primary analysis conclusions when a substantial number of subjects withdraw from treatment prematurely prior to experiencing an event of interest. We discuss how the methods that are widely used for primary analyses of time‐to‐event outcomes could be extended in a clinically meaningful and interpretable way to stress‐test the assumption of ignorable censoring. We focus on a ‘tipping point’ approach, the objective of which is to postulate sensitivity parameters with a clear clinical interpretation and to identify a setting of these parameters unfavorable enough towards the experimental treatment to nullify a conclusion that was favorable to that treatment. Robustness of primary analysis results can then be assessed based on clinical plausibility of the scenario represented by the tipping point. We study several approaches for conducting such analyses based on multiple imputation using parametric, semi‐parametric, and non‐parametric imputation models and evaluate their operating characteristics via simulation. We argue that these methods are valuable tools for sensitivity analyses of time‐to‐event data and conclude that the method based on piecewise exponential imputation model of survival has some advantages over other methods studied here. Copyright © 2016 John Wiley & Sons, Ltd.