Statistics for weighing benefits and harms in a proposed genetic substudy of a randomized cancer prevention trial

Summary.  When evaluating potential interventions for cancer prevention, it is necessary to compare benefits and harms. With new study designs, new statistical approaches may be needed to facilitate this comparison. A case in point arose in a proposed genetic substudy of a randomized trial of tamoxifen versus placebo in asymptomatic women who were at high risk for breast cancer. Although the randomized trial showed that tamoxifen substantially reduced the risk of breast cancer, the harms from tamoxifen were serious and some were life threaten-ing. In hopes of finding a subset of women with inherited risk genes who derive greater bene-fits from tamoxifen, we proposed a nested case–control study to test some trial subjects for various genes and new statistical methods to extrapolate benefits and harms to the general population. An important design question is whether or not the study should target common low penetrance genes. Our calculations show that useful results are only likely with rare high penetrance genes.     

Statistik für bivariate gemischte Poisson–Prozesse am Beispiel der Kraftfahrthaftpflichtversicherung

Zusammenfassung: In diesem Artikel wird der Weg von einem univariaten gemischten Poisson–Prozess, der in vielen Bereichen zum Z?hlen von Ereignissen benutzt wird, zu einem bivariaten gemischten Poisson–Prozess aufgezeigt. Dazu werden einige Eigenschaften des bivariaten Prozesses angegeben. Im zweiten Teil der Arbeit wird gezeigt, wie mit Hilfe dieses Prozesses der übergang von einem herk?mmlichen Bonus–Malus–System in der Kraftfahrthaftpflichtversicherung zu einem Bonus–Malus–System mit Berücksichtigung der Schadenart beschritten werden kann. Dazu wird zuerst eine Modellprüfung der gegebenen Daten vorgenommen und sodann werden für verschiedene mischende Verteilungen die Verteilungsparameter gesch?tzt und Nettopr?mien angegeben sowie die Prognosegenauigkeit getestet.

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Summary: In this paper we show that the model of the bivariate mixed Poisson process arises in a natural way from the univariate mixed Poisson process, which is used in several areas for counting certain events. Furthermore we state some properties of the bivariate process. In the second part of the paper we illustrate how by means of the bivariate mixed Poisson process a bonus–malus system handling different types of accidents can be derived from the classical bonus–malus system in third–party liability insurance. To this end we first check the model on the given data and then estimate distribution parameters and compute net premiums for different mixing distributions as well as test the prediction probabilities.

* Vortrag am Dresdner Forum zur Versicherungsmathematik: Tarifierung in Erst- und Rückversicherung am 25. Juni 2004. Für die Unterstützung zu dieser Arbeit m?chte der Autor Lothar Partzsch, Klaus D. Schmidt (beide Dresden) und Friedemann Spies (München) recht herzlich danken.     

The Role of Cancer Risk in the Regulation of Industrial Pollution

The extent of carcinogen regulation under existing U.S. environmental statutes is assessed by developing measures of the scope and stringency of regulation. While concern about cancer risk has played an important political role in obtaining support for pollution control programs, it has not provided the predominant rationale for most regulatory actions taken to date. Less than 20% of all standards established to limit concentrations of chemicals in various media address carcinogens. Restrictions on chemical use are more frequently based on concerns about noncancer human health or ecological effects. Of the chemicals in commercial use which have been identified as potential human carcinogens on the basis of rodent bioassays, only a small proportion are regulated. There is an inverse relationship between the scope of regulatory coverage and the stringency of regulatory requirements: the largest percentages of identified carcinogens are affected by the least stringent requirements, such as information disclosure. Standards based on de minimis cancer risk levels have been established for only 10% of identified carcinogens and are restricted to one medium: water. Complete bans on use have affected very few chemicals. The general role that carcinogenicity now plays in the regulatory process is not dramatically different from that of other adverse human health effects: if a substance is identified as a hazard, it may eventually be subject to economically achievable and technically feasible restrictions.     

Healthy Barbs: Activism Confronts Mortality

Barbara Brenner, JD, was the Executive Director of Breast Cancer Action (BCA) from 1995–2010. Before that, she was a longtime activist in the anti-war movement and an attorney who, for most of her career, practiced public policy law. After she was diagnosed with breast cancer in 1993 at the age of 41, she took the helm of BCA. Under her leadership, the organization moved into a position of national advocacy—demanding research on the causes and prevention of breast cancer, including the role of industrial pollutants. Barbara started the “Think Before You Pink” campaign, encouraging people to question whether companies that display pink ribbons actually produce products that harm women's health or generate any funds to fight breast cancer. Her blog, “Healthy Barbs,” challenged readers to critique routine healthcare practices and policies. Barbara received numerous awards, including a Jefferson Award for Public Service in 2007, the Smith College Medal in 2012, and the ACLU-Northern California's Lola Hanzel Courageous Advocacy Award in 2012. Barbara had a recurrence of breast cancer in 1996. She died of complications associated with amyotrophic lateral sclerosis, ALS, on May 10, 2013.     

农业产业化龙头企业可持续发展战略研究——基于郑州市农业龙头企业发展的分析

农业产业化龙头企业发展到现在,迫切需要建立起自己的发展战略体系,以指导企业未来的经营与发展,使企业更好地适应越来越严峻的竞争形势。通过对郑州市农业龙头企业可持续发展问题的分析,提出我国农业产业化龙头企业可持续发展的战略。     

消费者展厅行为和参考质量效应对O2O供应链动态运营策略的影响

本文研究消费者展厅行为和参考质量效应对O2O供应链动态运营策略的影响问题。分析了集中决策、分散决策和制造商分担实体店服务成本决策3种模式下的制造商产品质量策略、实体店和电商平台的服务竞争策略,以及品牌商誉变化和企业利润等问题。并进行了价格、实体店访问比例和展厅行为强度对企业绩效的影响。研究发现：展厅行为会挫伤实体店提供服务的积极性,降低品牌商誉,从而损害制造商和实体店的利润水平;而消费者的这种搭便车行为会提高电商平台利润,但由于参考质量效应的存在,其提升空间有限。综合而言,展厅行为对供应链总体绩效不利。应对展厅行为的长期战略有：1)加强上下游的纵向合作,制造商分担实体店服务成本契约,能实现供应链总体绩效的帕累托改进。2)从受展厅行为影响最大的实体店角度,保持线下产品高定价、高服务水平,提升消费者支付意愿,全面提升实体店的品牌溢价能力,获取长久生存之道。     

The role of parenthood in shaping the gender wage gap – A comparative analysis of 26 European countries

We use cross-national data on 26 EU countries to estimate how parenthood contributes to the gender wage gap, and assess how institutional elements affect this relationship. We find that irrespective of cultural norms and policies, fathers receive a wage premium, which increases the gender gap. Motherhood gaps vary across countries. The highest gaps are seen in Eastern European countries, where policies and norms lead to long absences from work. Moderate to small penalties are found in Continental Europe, Anglo-Saxon and Nordic countries, alongside higher maternal employment. No motherhood penalties are found for Southern EU countries, where mothers return to work quickly or exit the labor market indefinitely.     

异质性技术视角下中国高技术制造业创新效率研究

目前,学术界对选取何种风险调整贴现率期限结构还存在争议,导致对同类投资项目得 出不同的管理指引意见． 针对这一争议,本文通过划分资本产出方式, 寻找影响贴现率结构的 主要因素． 研究表明,不确定的宏观经济产出和项目非系统风险共同影响风险溢价系数, 同时 风险溢价系数决定贴现率期限结构． 其中,当风险溢价系数大于某确定阈值, 贴现率随时间递 增; 其余情况表现为递减．     

我国新型农村社会养老保险经济支持能力研究

老农保的失败让人们对新农保充满期待的同时也存有几分担忧,他们担心农民的经济承受力。更怕财政不堪重负。为坚定领导层试点、推广新农保的信心和决心,加快新农保发展步伐,本文在测算新型农村社会养老保险的经济负担的基础上,对农民个人和政府两方面的经济支持能力进行分析,认为只要制度设计合理,农民个人和政府是有能力承担这部分支出的。     

Bayesian robustness of the compound Poisson distribution under bidimensional prior: an application to the collective risk model

The distribution of the aggregate claims in one year plays an important role in Actuarial Statistics for computing, for example, insurance premiums when both the number and size of the claims must be implemented into the model. When the number of claims follows a Poisson distribution the aggregated distribution is called the compound Poisson distribution. In this article we assume that the claim size follows an exponential distribution and later we make an extensive study of this model by assuming a bidimensional prior distribution for the parameters of the Poisson and exponential distribution with marginal gamma. This study carries us to obtain expressions for net premiums, marginal and posterior distributions in terms of some well-known special functions used in statistics. Later, a Bayesian robustness study of this model is made. Bayesian robustness on bidimensional models was deeply treated in the 1990s, producing numerous results, but few applications dealing with this problem can be found in the literature.