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1.
Comparative risk assessment is an evaluation process designed to rank environmental problems based on the severity of potential hazards. The purpose of this paper is to provide an effective statistical approach to analyze perceived environmental risks. Environmental problems, evaluative criteria, and other potential moderator variables need to be determined first, and then the risk perception data collected. Repeated measures analysis is used to first test for interactions between environmental problems and potential moderator variables. If there are no significant interactions, then the risk difference among environmental problems is tested unconditionally; otherwise the risk difference is tested conditionally. Cluster analysis for environmental problems is performed only when the risk difference is significant. The clustering results can be objectively determined by using the simultaneous T2 confidence intervals. Risk-based priority setting is made according to the clusters obtained. To illustrate this approach, an empirical study of comparative socioeconomic risks in Taiwan was conducted. Socioeconomic impacts areas including social security, quality of life, production cost, investment willingness, and economic resources are used as evaluative criteria. Results indicate that selected impact areas do affect relative risk differences among 24 environmental problems, and the difference is significant for each area. Therefore, cluster analysis is conducted separately for each impact area. Risk-based priority settings for clusters of environmental problems are reported.  相似文献   

2.
This article presents a process for an integrated policy analysis that combines risk assessment and benefit-cost analysis. This concept, which explicitly combines the two types of related analyses, seems to contradict the long-accepted risk analysis paradigm of separating risk assessment and risk management since benefit-cost analysis is generally considered to be a part of risk management. Yet that separation has become a problem because benefit-cost analysis uses risk assessment results as a starting point and considerable debate over the last several years focused on the incompatibility of the use of upper bounds or "safe" point estimates in many risk assessments with benefit-cost analysis. The problem with these risk assessments is that they ignore probabilistic information. As advanced probabilistic techniques for risk assessment emerge and economic analysts receive distributions of risks instead of point estimates, the artificial separation between risk analysts and the economic/decision analysts complicates the overall analysis. In addition, recent developments in countervailing risk theory suggest that combining the risk and benefit-cost analyses is required to fully understand the complexity of choices and tradeoffs faced by the decisionmaker. This article also argues that the separation of analysis and management is important, but that benefit-cost analysis has been wrongly classified into the risk management category and that the analytical effort associated with understanding the economic impacts of risk reduction actions need to be part of a broader risk assessment process.  相似文献   

3.
Ten years ago, the National Academy of Science released its risk assessment/risk management (RA/RM) “paradigm” that served to crystallize much of the early thinking about these concepts. By defining RA as a four-step process, operationally independent from RM, the paradigm has presented society with a scheme, or a conceptually common framework, for addressing many risky situations (e.g., carcinogens, noncarcinogens, and chemical mixtures). The procedure has facilitated decision-making in a wide variety of situations and has identified the most important research needs. The past decade, however, has revealed that additional progress is needed. These areas include addressing the appropriate interaction (not isolation) between RA and RM, improving the methods for assessing risks from mixtures, dealing with “adversity of effect,” deciding whether “hazard” should imply an exposure to environmental conditions or to laboratory conditions, and evolving the concept to include both health and ecological risk. Interest in and expectations of risk assessment are increasing rapidly. The emerging concept of “comparative risk” (i.e., distinguishing between large risks and smaller risks that may be qualitatively different) is at a level comparable to that held by the concept of “risk” just 10 years ago. Comparative risk stands in need of a paradigm of its own, especially given the current economic limitations. “Times are tough; Brother, can you paradigm?”  相似文献   

4.
基于追随者银行的企业项目总体风险评价问题是指当有银行作为先行者介入一个项目时,后续的其它另一个银行作为追随者银行需要将先行者银行的信用风险和所要参与投资的企业项目风险综合加以考虑、从而独立判断项目投资的总体风险大小并进行投资决策。由于任何一家银行都只能熟悉某一些领域、某一些地区、某一些国家的项目,这就导致追随者银行在无法充分掌握项目信息时,需要以先行者银行的信用风险大小为参照物之一来推断企业项目的总体风险,这不仅仅对投资和贷款业务开展较晚的例如中国邮政储蓄银行这样的商业银行有着重要现实意义,而且对所有商业银行的投资活动都有重要的指导意义。通过先行者银行信用风险与项目风险反映企业项目总体风险,本研究建立了基于Copula函数的追随者银行的企业项目总体风险评价模型。本文主要的创新与特色是通过确定先行者银行的信用风险RF与项目风险Rp的函数关系,进而确定企业项目总体风险RT,解决了追随者银行所要测算企业项目风险的问题。总体风险模型的稳定性检验表明,在95%的置信水平下,对追随者银行来说,不论多大样本,其所要投资项目的总体风险中的先行者银行信用风险RF与所要投资的项目风险Rp的重要程度分别为W1=0.428、W2=0.572。  相似文献   

5.
《Omega》2001,29(1):97-109
The assessment of financial risks is a problem of major interest for corporate entities (organizations, financial institutions, firms, etc.). The vulnerable economic and financial environments necessitate the development of operational approaches to measure and control financial risks. Most of the methodologies that have been proposed in the past employ a probabilistic notion of risk. This paper proposes an alternative approach to measure financial risks, considering their multidimensional nature. The proposed approach is based on the multicriteria decision aid (MCDA) method Multi-Group Hierarchical DIScrimination (M.H.DIS). The aim of the M.H.DIS method within the financial risk assessment context is to develop a set of additive utility functions that classify the considered alternatives (firms, investment projects, portfolios, countries, etc.) into predefined risk classes. The efficiency of the method is illustrated through a case study regarding the country risk assessment problem. Using the M.H.DIS method a discrimination model is developed that classifies the countries into four groups, and measures the corresponding creditworthiness and risk of the countries. Several validation tests are performed in order to compare the classification results obtained through M.H.DIS to the results obtained through multiple discriminant analysis.  相似文献   

6.
Intuitive Toxicology: Expert and Lay Judgments of Chemical Risks   总被引:2,自引:0,他引:2  
Human beings have always been intuitive toxicologists, relying on their senses of sight, taste, and smell to detect harmful or unsafe food, water, and air. As we have come to recognize that our senses are not adequate to assess the dangers inherent in exposure to a chemical substance, we have created the sciences of toxicology and risk assessment to perform this function. Yet despite this great effort to overcome the limitations of intuitive toxicology, it has become evident that even our best scientific methods still depend heavily on extrapolations and judgments in order to infer human health risks from animal data. Many observers have acknowledged the inherent subjectivity in the assessment of chemical risks and have indicated a need to examine the subjective or intuitive elements of expert and lay risk judgments. We have begun such an examination by surveying members of the Society of Toxicology and the lay public about basic toxicological concepts, assumptions, and interpretations. Our results demonstrate large differences between toxicologists and laypeople, as well as differences between toxicologists working in industry, academia, and government. In addition, we find that toxicologists are sharply divided in their opinions about the ability to predict a chemical's effect on human health on the basis of animal studies. We argue that these results place the problems of risk communication in a new light. Although the survey identifies misconceptions that experts should clarify for the public, it also suggests that controversies over chemical risks may be fueled as much by limitations of the science of risk assessment and disagreements among experts as by public misconceptions.  相似文献   

7.
在项目投资过程中不但面临项目风险,同时还面临背景风险,且背景风险与项目风险之间往往存在着一定的相关性。文章在已有研究的基础上,针对考虑背景风险的项目投资决策问题,分析了风险之间的相关性及相关程度对投资决策的影响。首先讨论了加性背景风险和乘性背景风险单独存在时,背景风险与项目风险之间的相关性对投资决策的影响;其次构建了两种背景风险同时存在情形下的投资模型,进而通过蒙特卡罗仿真方法给出不同相关程度下的仿真结果,在此基础上分析两种背景风险与项目风险之间的相关性及相关程度对投资决策的影响并给出相关研究结论。  相似文献   

8.
D. Wayne Berman 《Risk analysis》2011,31(8):1308-1326
Given that new protocols for assessing asbestos‐related cancer risk have recently been published, questions arise concerning how they compare to the “IRIS” protocol currently used by regulators. The newest protocols incorporate findings from 20 additional years of literature. Thus, differences between the IRIS and newer Berman and Crump protocols are examined to evaluate whether these protocols can be reconciled. Risks estimated by applying these protocols to real exposure data from both laboratory and field studies are also compared to assess the relative health protectiveness of each protocol. The reliability of risks estimated using the two protocols are compared by evaluating the degree with which each potentially reproduces the known epidemiology study risks. Results indicate that the IRIS and Berman and Crump protocols can be reconciled; while environment‐specific variation within fiber type is apparently due primarily to size effects (not addressed by IRIS), the 10‐fold (average) difference between amphibole asbestos risks estimated using each protocol is attributable to an arbitrary selection of the lowest of available mesothelioma potency factors in the IRIS protocol. Thus, the IRIS protocol may substantially underestimate risk when exposure is primarily to amphibole asbestos. Moreover, while the Berman and Crump protocol is more reliable than the IRIS protocol overall (especially for predicting amphibole risk), evidence is presented suggesting a new fiber‐size‐related adjustment to the Berman and Crump protocol may ultimately succeed in reconciling the entire epidemiology database. However, additional data need to be developed before the performance of the adjusted protocol can be fully validated.  相似文献   

9.
There are two broad categories of risk affecting supply chain design and management: (1) risks arising from the problems of coordinating supply and demand, and (2) risks arising from disruptions to normal activities. This paper is concerned with the second category of risks, which may arise from natural disasters, from strikes and economic disruptions, and from acts of purposeful agents, including terrorists. The paper provides a conceptual framework that reflects the joint activities of risk assessment and risk mitigation that are fundamental to disruption risk management in supply chains. We then consider empirical results from a rich data set covering the period 1995–2000 on accidents in the U. S. Chemical Industry. Based on these results and other literature, we discuss the implications for the design of management systems intended to cope with supply chain disruption risks.  相似文献   

10.
Venture capitalists (VCs) face additional risks and costs when they invest in firms located in geographically remote countries or in countries whose institutions differ substantially from those in their home countries. Our study considers foreign VCs ' prospect of overcoming these investment obstacles as a rationale for syndicating with local VCs from the investment countries. Through such syndication, foreign VCs may obtain easier access to investment opportunities, improve the risk allocation and face lower information costs. Using a novel dataset of worldwide deals, we draw a diametrically opposed picture for the two kinds of distance: our results lend support to the conjecture that the obstacles of great institutional distance cannot be overcome with the help of a local VC, whereas those of great geographical distance can.  相似文献   

11.
国家风险是我国企业海外投资优先考虑的外部因素,其构成的多维度性、不同维度风险之间关联的客观存在性以及企业决策者差异化的偏好等特点,加剧了海外投资国家风险评估的难度。本文引入风险关联和决策者偏好,提出一种二元语义DEMATEL法、基尼系数客观赋权法与VIKOR法相结合的海外投资国家风险评估方法来量化风险关联,并从主客观集成视角确定风险评估指标权重,以期得到不同决策机制下的投资风险国别排序。随即,通过采集“一带一路”沿线63个国家的数据开展实证分析,验证所提出方法的有效性,并对结果进行分析与讨论。研究结果能够为海外投资区位选择提供必要的决策支持,也能够对我国企业海外投资风险防范、推动共建“一带一路”高质量发展有所裨益。  相似文献   

12.
Life cycle assessment (LCA) and risk assessment are operationally different but share the common purpose of supporting decisions about reducing threats to human welfare. Both analysis methods also involve a complex mixture of science and value judgments reflecting epistemological as well as moral and esthetic values. The inability of risk assessment and LCA to be "value free" has been a source of considerable controversy in both communities. Recognition of the contingent and social nature of human interpretation of the risks and environmental impacts created by public and private decisions has led to an increased appreciation of the importance of involving interested and affected parties in risk characterization. Comparison of the value-based nature of LCA and risk assessment demonstrates the need for participation in LCA. Although the need for participation by affected parties in decision-making processes is gaining acceptance, there is little agreement as to how participation should be structured. Risk assessment and LCA have a shared need for research examining the design and analysis of participation processes appropriate to a given decision context. A proposed framework recommends participation strategies designed to enhance the effectiveness of policy-driven analyses such as risk assessment and LCA based on the level of trust that interested and affected parties have for other policy participants.  相似文献   

13.
《Risk analysis》2018,38(2):392-409
The relative contributions of exposure pathways associated with cattle‐manure‐borne Escherichia coli O157:H7 on public health have yet to be fully characterized. A stochastic, quantitative microbial risk assessment (QMRA) model was developed to describe a hypothetical cattle farm in order to compare the relative importance of five routes of exposure, including aquatic recreation downstream of the farm, consumption of contaminated ground beef processed with limited interventions, consumption of leafy greens, direct animal contact, and the recreational use of a cattle pasture. To accommodate diverse environmental and hydrological pathways, existing QMRAs were integrated with novel and simplistic climate and field‐level submodels. The model indicated that direct animal contact presents the greatest risk of illness per exposure event during the high pathogen shedding period. However, when accounting for the frequency of exposure, using a high‐risk exposure‐receptor profile, consumption of ground beef was associated with the greatest risk of illness. Additionally, the model was used to evaluate the efficacy of hypothetical interventions affecting one or more exposure routes; concurrent evaluation of multiple routes allowed for the assessment of the combined effect of preharvest interventions across exposure pathways—which may have been previously underestimated—as well as the assessment of the effect of additional downstream interventions. This analysis represents a step towards a full evaluation of the risks associated with multiple exposure pathways; future incorporation of variability associated with environmental parameters and human behaviors would allow for a comprehensive assessment of the relative contribution of exposure pathways at the population level.  相似文献   

14.
金融压力指数能较好地实时反映一国金融体系承受风险的压力状况,帮助决策者和市场参与各方及时准确地前瞻性评估潜在风险来临时可能承受的金融压力水平。根据各市场对整个金融体系的影响程度,利用CDF-信用加总权重法确定各指标权重,构建了包括银行、股票、外汇、保险四大市场的我国金融压力指数测度模型体系。实证研究表明,我国金融压力的阶段性特征明显,在国际金融危机发生时,往往伴随着高的金融压力;我国金融压力主要来自于银行部门,随着近年来我国银行治理水平提高和资本市场发展,银行部门压力指数正缓慢下降,股票市场压力却逐渐上升;外汇市场和保险市场压力指数长期保持在低位运行。有效性检验表明,来自我国FSI的冲击在滞后6个季度会对宏观经济产生显著的不利影响。  相似文献   

15.
The need for a framework to evaluate the risks inherent in dealing with different countries is widely recognized. International financial institutions, government agencies and major corporations have in recent years established formal systems of risk assessment as an important input to their operational and planning decisions. It is important to understand the basic thinking underlying the mechanical approach to risk analysis and the results must be treated with care. A structured approach to the evaluation of international risks provides the necessary analytical framework.  相似文献   

16.
17.
国际组合投资涉及多币种汇率风险,分别使用双边货币期货进行套保要承担较高套保成本。参考美元指数期货的实践,本文提出基于人民币指数期货的综合套保策略。实证结果表明,无论对于单个货币资产还是分散化投资的国际股指、债指组合,引入人民币指数期货能够显著降低收益率波动,提高抵御汇率波动的能力,同时拓展收益空间,是有效的汇率风险综合套保工具;人民币指数期货套保效率显著优于货币期货篮子,在发达国家股指市场表现更加突出。采用基于指数加权移动平均模型(EWMA)的动态套保策略,使得人民币指数期货收益对股指或债指市场波动敏感度降低,在市场极端状况时仍能保持相对中性。  相似文献   

18.
Chabane Mazri 《Risk analysis》2017,37(11):2053-2065
The concept of emergence in risk management can be seen as a revealing symptom of the increasing need for organizations to update their portfolio of risks and opportunities in a rapidly changing and highly competitive environment. Accordingly, the concept of emerging risks has been widely discussed in both scientific and business communities, with, however, a lack of agreement as to whether we should distinguish these risks from others and, if so, what should be the adopted approach for their governance. After reviewing a large set of definitions and conceptions of emerging risks, this article aims at exploring the existence of distinctive features allowing the characterization of a risk as emerging or not. First, we will demonstrate that the features used in the various definitions are ineffective to achieve this distinction. Furthermore, we will argue that all events and consequences associated with risks are or have been states of nature that emerged from complex interactions involving combinations of hazardous activities and stakes. Accordingly, emerging risks are no longer a specific category of risks; they are rather an early step in every risk life cycle that deserves specific governance approaches.  相似文献   

19.
Very little quantitative analysis is currently available on the cumulative effects of exposure to multiple hazardous agents that have either similar or different mechanisms of action. Over the past several years, efforts have been made to develop the methodologies for risk assessment of chemical mixtures, but mixed exposures to two or more dissimilar agents such as radiation and one or more chemical agents have not yet been addressed in any substantive way. This article reviews the current understanding of the health risks arising from mixed exposures to ionizing radiation and specific chemicals. Specifically discussed is how mixed radiation/chemical exposures, when evaluated in aggregation, were linked to chronic health endpoints such as cancer and intermediate health outcomes such as chromosomal aberrations. Also considered is the extent to which the current practices are consistent with the scientific understanding of the health risks associated with mixed-agent exposures. From this the discussion moves to the research needs for assessing the cumulative health risks from aggregate exposures to ionizing radiation and chemicals. The evaluation indicates that essentially no guidance has been provided for conducting risk assessment for two agents with different mechanisms of action (i.e., energy deposition from ionizing radiation versus DNA interactions with chemicals) but similar biological endpoints (i.e., chromosomal aberrations, mutations, and cancer). The literature review also reveals the problems caused by the absence of both the basic science and an appropriate evaluation framework for the combined effects of mixed-agent exposures. This makes it difficult to determine whether there is truly no interaction or somehow the interaction is masked by the scale of effect observation or inappropriate dose-response assumptions.  相似文献   

20.
Import Security: Assessing the Risks of Imported Food   总被引:1,自引:0,他引:1       下载免费PDF全文
We use data on food import violations from the FDA Operational and Administrative System for Import Support (OASIS) to address rising concerns associated with imported food, quantify import risks by product and by country of origin, and explore the usefulness of OASIS data for risk assessment. In particular, we assess whether there are significant trends in violations, whether import violations can be used to quantify risks by country and by product, and how import risks depend on economic factors of the country of origin. The results show that normalizing import violations by volume of imports provides a meaningful indicator of risk. We then use regression analysis to characterize import risks.  Using this model, we analyze import risks by product type, violation type, and economic factors of the country of origin.  We find that OASIS data are useful in quantifying food import risks, and that the rate of refusals provides a useful decision tool for risk management.  Furthermore, we find that some economic factors are significant indicators of food import risk by country.  相似文献   

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