Identifiability of distributions under competing risks and complementary risks model

Let X₁,X₂,…,X_p be p random variables with cdf's F₁(x),F₂(x),…,F_p(x)respectively. Let U = min(X₁,X₂,…,X_p) and V = max(X₁,X₂,…,X_p).In this paper we study the problem of uniquely determining and estimating the marginal distributions F₁,F₂,…,F_p given the distribution of U or of V.

First the problem of competing and complementary risks are introduced with examples and the corresponding identification problems are considered when the X₁'s are independently distributed and U(V) is identified, as well as the case when U(V) is not identified. The case when the X₁'s are dependent is considered next. Finally the problem of estimation is considered.     

Maximum likelihood ridge displays

I illustrate likelihood methods for estimating the consequences of shrinkage along any ridge path as well as methods for picking a two-hyperparameter path of optimal curvature and the optimal point on that path. In addition to my published "classical" methods, I also illustrate both the empirical Bayes and the random coefficient maximum likelihood approaches. Traces of risks for known parameters and losses for simulated responses are followed by traces of estimates that can reveal the same general information.     

The EPA Health Risk Assessment of Methylcyclopentadienyl Manganese Tricarbonyl (MMT)

This paper describes the U.S. Environmental Protection Agency's assessment of potential health risks associated with the possible widespread use of a manganese (Mn)-based fuel additive, methylcyclopentadienyl manganese tricarbonyl (MMT). This assessment was significant in several respects and may be instructive in identifying certain methodological issues of general relevance to risk assessment. A major feature of the inhalation health risk assessment was the derivation of Mn inhalation reference concentration (RfC) estimates using various statistical approaches, including benchmark dose and Bayesian analyses. The exposure assessment component used data from the Particle Total Exposure Assessment Methodology (PTEAM) study and other sources to estimate personal exposure levels of particulate Mn attributable to the permitted use of MMT in leaded gasoline in Riverside, CA, at the time of the PTEAM study; on this basis it was then possible to predict a distribution of possible future exposure levels associated with the use of MMT in all unleaded gasoline. Qualitative as well as quantitative aspects of the risk characterization are summarized, along with inherent uncertainties due to data limitations.     

Impact of Hazardous Substances Regulations on Small Firms in Delaware and New Jersey

Regulations under the 1990 Amendments to the Clean Air Act impose significant requirements on firms handling hazardous chemicals. The nature of the regulations would suggest that small firms, because of limited resources and other structural limitations, would experience more difficulty complying with the regulations than large firms. To understand the difficulties imposed by the regulations on small firms, we interviewed ten small firms in Delaware and New Jersey, states with existing hazardous regulations similar to those being considered by the U.S. Environmental Protection Agency, and evaluated their responses to state regulations. The impacts of the environmental regulations on the firms and on the risk levels of their businesses are discussed. Propositions for research into small firms compliance are developed. Possible means for reducing the regulatory burden on small firms while enhancing regulatory effectiveness are suggested.     

产业集群品牌风险与规避措施探析

集群品牌是集群的共有财富,是集群产品提高竞争力的重要途径。但集群品牌的公共物品属性会造成集群内企业对其维护与发展的投入不足,而且个别企业的投机行为可能会产生"多米诺骨牌"效应,造成"公共地风险",给集群品牌带来破坏。为规避集群品牌风险,需要企业、政府和中介机构等多方面共同努力,通过申请注册集群商标、完善质量认证监督体系、多渠道开展集群品牌营销活动、集体应对贸易摩擦等措施来做好集群品牌的发展与维护工作。     

网络突发事件的生成与治理： 基于风险的社会放大框架的分析

从风险的角度看,网络突发事件就是一个以网络为主要传播媒介的风险的社会放大过程,也是一个在网络与社会现实不断互动中放大社会风险的系统.本文以风险的社会放大框架为分析工具,对网络突发事件的酝酿与生成机制进行深入的分析,并在此基础上,提出了要以风险治理为切入点对网络突发事件进行治理,从风险控制转向风险沟通,重构风险传播中政府、媒体和公众三者关系等若干政策性建议.     

天命、道德和民意——从政治正当性看殷周政权转换

殷周政权转换之际天命伦理化,天命观念发生了从"有命在天"到"天命靡常"的转变,"敬德"思想取代了"敬神"思想,"保民"思想在西周初年兴起。这一时期的思想变革展现出了中国古代政权自我确证是道德的思想路径,即天命是善的,生成道德的政权,道德的政权敬德保民,消灭不道德的政权。这有别于西方政治寻求政权被他者证明是道德的思想路径。     

行政和解中滥用伦理妥协的风险及其对策

适当地运用伦理妥协手段可以解除行政和解中的两难处境,但在行政和解过程中滥用伦理妥协,就会引发伦理风险,威胁行政和解制度的良性运行、消减政府的公信力、促使行政人员道德坠落。构建行政和解伦理监督机制、规范伦理妥协适用原则和条件、提高公职人员道德素养是有效防范道德风险的必然选择。     

P2P系统中的著作权侵权责任探析

P2P系统的应用,使得作品的传播变得更加方便与快捷,也使得对作品的侵权越来越成为可能,为了寻求文化艺术作品的传播与版权人利益保护之间的平衡,从网络技术和法律方法相结合的角度,研究了P2P系统中的著作权侵权问题。认为P2P系统中的著作权侵权应当适用过错责任的归责原则。根据这一原则,只要ICP所提供的内容侵权,就需要承担侵权责任,软件提供商在明知或应知软件侵权的情况下仍然提供服务也应当承担侵权责任,软件经营者则可以适用＂通知与删除＂规则,在有证据表明有人利用P2P系统侵害著作权的情况下,软件经营者应当停止相应服务,否则就应当承担侵权责任。而对于P2P用户,则可要求其对其共享文件夹中的侵权作品承担侵权责任。     

国际贸易中海运提单的风险及防范策略研究

海运提单是国际贸易中极其关键的单据,合理合法地使用海运提单对于国际贸易的繁荣和发展意义非凡。但是,在国际贸易中,由于货物流转速度加快、相关法律不健全等因素导致提单的不规范使用,引起倒签、预借等各种提单风险的发生。未来应通过加强对贸易伙伴的资信调查、选择合适的贸易术语、制定适宜的信用证条款等策略来防范海运提单风险的发生。