Credibility, Information Preferences, and Information Interests

The Seveso Directive of the European Union demands that information be provided to the public by companies and authorities about facts, risks, and behaviors related to hazardous facilities, in particular chemical facilities. On behalf of the Commission of the European Communities, a survey was run in five European countries on the credibility of various information sources. This article describes the results of the German study. 430 persons were interviewed with a questionnaire of 50 items, in particular about their perceptions and evaluations of technical risks, the credibility of sources of information about chemical risks, their preferences for receiving risk information from these sources, and their interests in receiving information. Major findings are great differences in credibility, differentiated information preferences, and strong information interests. Surprisingly, credibility played only a minor role with regard to the respondents'information preferences and interests.     

Nonparametric estimation of discrete hazard functions

A smoothing procedure for discrete time failure data is proposed which allows for the inclusion of covariates. This purely nonparametric method is based on discrete or continuous kernel smoothing techniques that gives a compromise between the data and smoothness. The method may be used as an exploratory tool to uncover the underlying structure or as an alternative to parametric methods when prediction is the primary objective. Confidence intervals are considered and alternative techniques of cross validation based choices of smoothing parameters are investigated.     

中小型钢铁贸易企业的融资问题

随着中小型钢铁贸易企业融资问题的日益突出,与其密切相关的融资风险问题逐步成为业界关注的热点。中小型钢铁贸易企业由于受各种因素影响,面临融资难的困境:中小型钢铁贸易企业融资需求大,上游钢厂的垄断性较高,下游企业议价能力强;中小型钢铁贸易企业融资难,银行授信难度大,多层次资本市场尚未形成,自身管理存在缺陷。融资风险是中小型钢铁贸易企业筹集资金时所面临的一大难题,融资风险产生的原因有很多:从内因上看,融资结构比例失调,融资的时机和方式选择不当,筹集的资金缺乏有效的管理和运用;从外因上看,包括政策性风险和金融市场风险等。对中小型钢铁贸易企业进行融资风险评估后发现:负债规模普遍过高、担保能力不强,中小型钢铁贸易企业实力较弱,抵质押物补偿性偏弱,经营风险大。对于中小型钢铁贸易企业,争取最大程度的融资并且合理控制融资风险,需要做好以下几个方面:针对行业特点制定稳健的金融决策;优化客户结构;认真做好贷前检查;加强中小型钢铁贸易企业的信贷管理。     

多元化选择:业务纵向整合的优势与风险分析

进入21世纪,以信息、资金、技术的跨国界流动为特征的全球化的趋势日益明显。伴随着中国加入WTO,我国市场的对外开放程度逐渐加大,国外企业纷纷进入。在这样一个充满竞争的市场中,没有一个行业可以持续地维持高额利润,也没有哪个企业能够轻易保持持续的竞争优势。这就迫使我国企业要在自己的主营业务稳定增长的基础上积极寻求企业的新的发展空间,多元化经营成为可选择的竞争战略之一。基于对众多国内外案例的研究,本文论述了企业多元化经营过程中业务纵向整合的优势与风险,对于我国企业的多元化决策,有一定的参考价值。     

A proportional hazards model for the analysis of doubly censored competing risks data

ABSTRACT

Competing risks data are common in medical research in which lifetime of individuals can be classified in terms of causes of failure. In survival or reliability studies, it is common that the patients (objects) are subjected to both left censoring and right censoring, which is refereed as double censoring. The analysis of doubly censored competing risks data in presence of covariates is the objective of this study. We propose a proportional hazards model for the analysis of doubly censored competing risks data, using the hazard rate functions of Gray (1988 Gray, R.J. (1988). A class of k-sample tests for comparing the cumulative incidence of a competing risk. Ann. Statist. 16:1141–1154.[Crossref], [Web of Science ®] , [Google Scholar]), while focusing upon one major cause of failure. We derive estimators for regression parameter vector and cumulative baseline cause specific hazard rate function. Asymptotic properties of the estimators are discussed. A simulation study is conducted to assess the finite sample behavior of the proposed estimators. We illustrate the method using a real life doubly censored competing risks data.     

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.     

Ranges of Measures of Association for Familial Binary Variables

Familial binary data occur in a wide range of scientific investigations. Numerous measures of association have been proposed in the literature for the study of intra-family dependence of the binary variables. These measures include correlations, odd ratios, kappa statistics, and relative risks. We study the permissible ranges of these measures of association such that a joint distribution exists for the familial binary variables. Our results are useful for developing efficient estimation methods for the measures of association.     

How to Perform an Ethical Risk Analysis (eRA)

Ethical analysis is often needed in the preparation of policy decisions on risk. A three‐step method is proposed for performing an ethical risk analysis (eRA). In the first step, the people concerned are identified and categorized in terms of the distinct but compatible roles of being risk‐exposed, a beneficiary, or a decisionmaker. In the second step, a more detailed classification of roles and role combinations is performed, and ethically problematic role combinations are identified. In the third step, further ethical deliberation takes place, with an emphasis on individual risk‐benefit weighing, distributional analysis, rights analysis, and power analysis. Ethical issues pertaining to subsidiary risk roles, such as those of experts and journalists, are also treated in this phase. An eRA should supplement, not replace, a traditional risk analysis that puts emphasis on the probabilities and severities of undesirable events but does not cover ethical issues such as agency, interpersonal relationships, and justice.     

Understanding public perceptions of genetically modified organisms in China: The role that heuristics play during digital media exposure

This study explicates the role that heuristics play in influencing Chinese public perceptions of genetically modified organisms (GMO) when they are exposed to digital media. According to the cognitive–affective continuum of heuristics, trust in scientists and negative emotions about GMOs are a cognition-oriented heuristic and an affect heuristic, respectively. The statistical results of an online survey (N?=?414) demonstrated that trust in scientists fully mediated digital media exposure and perceptions of the risks versus benefits of GMOs. In addition, negative emotions moderated the full mediation effect, showing that the indirect effect was stronger in individuals with low levels of negative emotions than in those with high levels of negative emotions. The mediating role of trust in scientists and the moderating role of negative emotions, the two heuristics applied in this study, indicated that when negative emotions were weak, laypeople were more likely to rely on scientists to judge the consequences of GMOs than systematically process the associated information by themselves. The findings have implications for reconsidering the importance of heuristic processing in building reasonable public perceptions of risk-laden technologies through the digital environment.