基于债权终止的可违约债券定价

已有实证结果表明流动性风险及其与违约风险的相关性是影响可违约债券收益率的重要因素,然而目前的研究还不能建立一种计算简便且同时包含流动性风险以及风险相关尤其是尾部相关性的定价模型。本文将流动性风险与违约风险都描述为债权终止事件驱动型的风险,从而可以利用与违约时间类似的出售时间来刻画流动性风险过程。基于债权终止事件的发生时间,本文拓展了简约模型以考虑流动性风险及风险相关性。与以往的研究相比,基于债权终止时间的模型具备诸多优势:模型简便适合大规模计算、允许时变流动性风险、包含尾部相关等较为丰富的风险相关性结构。数值算例表明,本文的模型能更好地刻画流动性风险溢价以及风险的尾部相关性对债券收益率曲线上下尾端的影响。     

独善其身还是唇亡齿寒：股价崩盘风险是否影响债券定价?

本文考察了在同一发行主体下,股价崩盘风险对债券定价的溢出效应。研究结果表明,当公司股价崩盘风险上升时,公司债券的表现也不能做到独善其身。股价崩盘风险越高的企业,其发行的债券在二级市场上的信用利差越高,而且这一效应在民营企业债券和低信用评级债券样本中的溢出程度更大。进一步的检验还显示:在风险承担水平较高、内部控制质量较差、会计信息不确定性越高的公司中,股价崩盘风险对债券信用利差的正向影响更为显著。本文从微观主体的角度考察了上市公司股价崩盘风险的经济后果,拓展了债券信用利差的跨市场影响因素研究,有助于理解中国股票和债券市场之间的联动关系,对于降低公司债券违约风险、维护资本市场平稳发展具有一定的启示意义。     

中国股市总流动性与资产定价关系实证研究

我们建立了一个包含市场风险和两种流动性风险的三因素资产定价模型,研究中国股市总的市场流动性风险是否在资产定价中得到了反映,其中流动性风险包括用协方差度量的市场收益对总流动性的敏感性风险和用方差度量的总流动性的波动性风险。研究结果表明,中国股市不仅存在显著的市场风险溢价,而且存在显著的流动性风险溢价,而流动性风险中市场收益对总流动性的敏感性风险对资产定价的影响更为显著。     

市场风险与违约风险同时存在下的最优资产配置

本文研究了当投资者同时面临市场风险(利率风险)和违约风险时,如何对可违约债券、国债、股票以及银行存款进行最优配置的问题。利用简约化模型来刻画可违约债券的违约风险,并给出其价格的动态方程。通过鞅方法给出了此优化问题的解析解,结果表明:股票的最优投资策略与Merton模型的结果相同;国债的最优投资策略是利率风险溢价的增函数;可违约债券的最优投资策略与跳跃(违约)风险溢价密切相关,只有当可违约债券的跳跃风险溢价大于1,即市场对跳跃风险进行风险补偿时,投资者才会持有可违约债券;否则,投资者对可违约债券的最优投资为零。     

债券投资者的选择:利率风险结构的阐述

作为投资者,当其购买债券时会面临购买何种债券的选择,因为这会给其带来不同的收益,那么,为什么会产生这种情况呢？这就需要对债券利率风险结构进行分析。从债券的违约风险,流动性风险和税收风险方面分析其对债券利率的影响,从而为投资者的选择提供理论依据。     

基于资产负债表关联的银行系统性风险研究

应用61家银行2009年年报数据对基于资产负债表关联的银行间市场双边传染风险进行研究,从信用违约和流动性风险角度对传染路径和资本损失进行估测,并深入分析银行间市场的不同结构对传染效应的影响,此外,本文还应用负二项式计数模型对系统重要性银行和易被传染银行的微观特征进行实证检验.研究得出:(1)在“完全分散型”市场结构假设下,我国银行间市场传染性风险极小;当考虑交易主体集中度并假设“相对集中型结构”时,系统性风险和传染效应将上升;当考虑违约风险和流动性风险联合冲击时,资本损失和风险传染的范围显著扩大.(2)大型国有银行处于银行间资本流动的中心环节,尤其中国银行和工商银行是传染风险发生的重要诱导来源.(3)影响银行在拆借市场中系统重要性的因素有银行类型、资产规模和风险头寸;而影响银行易受传染性的因素有银行类型、资本充足状况和风险暴露程度.     

含有违约风险的利率风险管理

旨在解决含有违约风险的利率风险管理问题,指出了在商业银行资产负债管理中含有违约风险债券利率风险管理问题研究的必要性,获得了违约风险债券久期的一般公式,建立了含有对违约风险的控制、平均绝对离差约束、平衡表其它相关约束以及目标约束等在内的商业银行利率风险管理的目标规划模型;并在给出数值实例的基础上,讨论了违约风险的存在对银行利率风险管理的影响.     

中小企业违约风险系统性和异质性测度——基于违约风险成分分析法的研究

与大中型企业相比，经济环境恶化或突发事件冲击使中小企业资产价值更易大幅下降，不仅单个企业违约风险急增，企业间的违约相关性也明显变大。然而不同类型中小企业违约风险变化特征仍有较大差异。为了更好测度中小企业违约风险、分析其相关性和差异性，本文在资产价值满足跳-扩散过程假定下，将或有权益分析法、组合违约风险分析与系统波动风险测度β相结合，把违约风险分解为系统成分和异质成分。系统成分越大，表明企业违约风险越易受外部经济环境和相关违约风险影响。异质成分越大则表明企业违约风险与自身异质性特征更为相关。实证研究表明，违约风险成分分析能较好解释中小企业违约风险的相关性和差异性，有助于违约风险分类管理。     

基于效用的永久性可转换债券定价

在不完备市场条件下,假设公司价值可以观测,公司只发行股票和不可赎回、不可违约的具有固定券息的永久性可转换债券,债券持有人有权利(但没有义务)按一定比例将债券转换为股票.基于可转换债券的结构式定价模型,给出债券持有人的最优转换策略,推导出可转换债券消费效用无差别价格的半封闭式解,利用有限差分方法,得到可转换债券的隐含价值(即消费效用无差别价格)以及可转换债券的最优消费策略和转换策略的数值解.研究结果表明,债券持有人的风险态度和非系统风险对最优转换策略和可转换债券的隐含价值有显著影响,与完备市场条件相比,风险厌恶情形可转换债券的转换触发水平和隐含价值较低,风险资产价格波动率越大,可转换债券的隐含价值越大.     

存在违约风险时的最优资产组合

本文研究了当存在违约风险时,一个代表性投资者投资于一个可违约债券、股票以及银行存款的最优资产配置问题。利用简约化模型来刻画可违约债券的违约风险,并给出其价格的动态过程。通过随机控制方法给出了此优化问题的解析解。结果表明跳跃(违约)风险的存在,使可违约债券的最优投资策略不再是连续函数。当可违约债券违约时,投资者对可违约债券的持有量为零;当债券未发生违约时,投资者对可违约债券的最优持有量主要受信用利差、违约强度以及投资期限的影响。     

Trust,Emotion, Sex,Politics, and Science: Surveying the Risk-Assessment Battlefield

Risk management has become increasingly politicized and contentious. Polarized views, controversy, and conflict have become pervasive. Research has begun to provide a new perspective on this problem by demonstrating the complexity of the concept risk and the inadequacies of the traditional view of risk assessment as a purely scientific enterprise. This paper argues that danger is real, but risk is socially constructed. Risk assessment is inherently subjective and represents a blending of science and judgment with important psychological, social, cultural, and political factors. In addition, our social and democratic institutions, remarkable as they are in many respects, breed distrust in the risk arena. Whoever controls the definition of risk controls the rational solution to the problem at hand. If risk is defined one way, then one option will rise to the top as the most cost-effective or the safest or the best. If it is defined another way, perhaps incorporating qualitative characteristics and other contextual factors, one will likely get a different ordering of action solutions. Defining risk is thus an exercise in power. Scientific literacy and public education are important, but they are not central to risk controversies. The public is not irrational. Their judgments about risk are influenced by emotion and affect in a way that is both simple and sophisticated. The same holds true for scientists. Public views are also influenced by worldviews, ideologies, and values; so are scientists' views, particularly when they are working at the limits of their expertise. The limitations of risk science, the importance and difficulty of maintaining trust, and the complex, sociopolitical nature of risk point to the need for a new approach—one that focuses upon introducing more public participation into both risk assessment and risk decision making in order to make the decision process more democratic, improve the relevance and quality of technical analysis, and increase the legitimacy and public acceptance of the resulting decisions.     

Perceived Risk, Trust, and Democracy

Risk management has become increasingly politicized and contentious. Polarized views, controversy, and overt conflict have become pervasive. Risk-perception research has recently begun to provide a new perspective on this problem. Distrust in risk analysis and risk management plays a central role in this perspective. According to this view, the conflicts and controversies surrounding risk management are not due to public ignorance or irrationality but, instead, are seen as a side effect of our remarkable form of participatory democracy, amplified by powerful technological and social changes that systematically destroy trust. Recognizing the importance of trust and understanding the "dynamics of the system" that destroys trust has vast implications for how we approach risk management in the future.     

The Theory of Risk Homeostasis: Implications for Safety and Health

No strategy for countermeasure design or future directions of research in the areas of human behavior which leads to traffic accidents or lifestyle-related diseases can be rationally developed without an acceptable working theory of human behavior in these domains. For this purpose, an attempt has been made to conceptually integrate the available evidence with respect to the role of human behavior in the causation of road accidents. From this integrative effort it would seem that the accident rate is ultimately dependent on one factor only, the target level of risk in the population concerned which acts as the reference variable in a homeostatic process relating accident rate to human motivation. Various policy tactics for the purpose of modifying this target level of risk have been pointed out and the theory of risk homeostasis has been speculatively extended to the areas of lifestyle-dependent morbidity and mortality.     

Risk Comparisons, Conflict, and Risk Acceptability Claims

Despite many claims for and against the use of risk comparisons in risk communication, few empirical studies have explored their effect. Even fewer have examined the public's relative preferences among different kinds of risk comparisons. Two studies, published in this journal in 1990 and 2003, used seven measures of "acceptability" to examine public reaction to 14 examples of risk comparisons, as used by a hypothetical factory manager to explain risks of his ethylene oxide plant. This study examined the effect on preferences of scenarios involving low or high conflict between the factory manager and residents of the hypothetical town (as had the 2003 study), and inclusion of a claim that the comparison demonstrated the risks' acceptability. It also tested the Finucane et al. (2000) affect hypothesis that information emphasizing low risks-as in these risk comparisons-would raise benefits estimates without changing risk estimates. Using similar but revised scenarios, risk comparison examples (10 instead of 14), and evaluation measures, an opportunity sample of 303 New Jersey residents rated the comparisons, and the risks and benefits of the factory. On average, all comparisons received positive ratings on all evaluation measures in all conditions. Direct and indirect measures showed that the conflict manipulation worked; overall, No-Conflict and Conflict scenarios evoked scores that were not significantly different. The attachment to each risk comparison of a risk acceptability claim ("So our factory's risks should be acceptable to you.") did not worsen ratings relative to conditions lacking this claim. Readers who did or did not see this claim were equally likely to infer an attempt to persuade them to accept the risk from the comparison. As in the 2003 article, there was great individual variability in inferred rankings of the risk comparisons. However, exposure to the risk comparisons did not reduce risk estimates significantly (while raising benefit estimates), and Conflict-Claim respondents found the risk of the hypothetical factory less acceptable than No-Conflict respondents. Results suggest that neither risk comparisons nor risk acceptability claims are automatically anathema to audiences, but they may have tiny or unintended effects on audience judgments about risky situations.     

Taxonomic Analysis of Perceived Risk: Modeling Individual and Group Perceptions Within Homogeneous Hazard Domains

Previous studies of risk perception have typically focused on the mean judgments of a group of people regarding the riskiness (or safety) of a diverse set of hazardous activities, substances, and technologies. This paper reports the results of two studies that take a different path. Study 1 investigated whether models within a single technological domain were similar to previous models based on group means and diverse hazards. Study 2 created a group taxonomy of perceived risk for only one technological domain, railroads, and examined whether the structure of that taxonomy corresponded with taxonomies derived from prior studies of diverse hazards. Results from Study 1 indicated that the importance of various risk characteristics in determining perceived risk differed across individuals and across hazards, but not so much as to invalidate the results of earlier studies based on group means and diverse hazards. In Study 2, the detailed analysis of railroad hazards produced a structure that had both important similarities to, and dissimilarities from, the structure obtained in prior research with diverse hazard domains. The data also indicated that railroad hazards are really quite diverse, with some approaching nuclear reactors in their perceived seriousness. These results suggest that information about the diversity of perceptions within a single domain of hazards could provide valuable input to risk-management decisions.     

风险相关性下的信用风险、市场风险和操作风险集成度量

商业银行各种风险之间相关性的存在,对其整体风险的度量产生重要影响。本文针对商业银行的信用风险、市场风险和操作风险这三类主要风险,在考虑相关性基础上给出了风险集成过程,通过copula函数和蒙特卡洛模拟方法计算了商业银行的整体风险,同时研究了风险分散化效应和在不同copula函数下整体风险的变化情况。最后以主流文献中的数据做了实证分析,结果显示本文提出方法能够很好的描述风险损失之间的相关性,同时在能够抵御相同风险的情况下考虑相关性下的在险值与简单相加得到的在险值相比要小,这能为银行业提高资金利用率提供了一定的理论和方法依据。     

供应链提前期风险空间传递机理与控制策略

针对供应链结构特性,本文分析了供应链提前期风险在链状供应链上的空间传递机理;根据风险因素作用的特点,将提前期风险划分为节点企业自身提前期风险、物流延期风险和传递风险。在此基础上,构建了供应链提前期风险空间传递模型和供应链提前期风险控制机理框架,并提出了关键的控制策略;最后通过算例分析验证了模型的有效性。     

The Use of Individual and Societal Risk Criteria Within the Dutch Flood Safety Policy—Nationwide Estimates of Societal Risk and Policy Applications

The Dutch government is in the process of revising its flood safety policy. The current safety standards for flood defenses in the Netherlands are largely based on the outcomes of cost‐benefit analyses. Loss of life has not been considered separately in the choice for current standards. This article presents the results of a research project that evaluated the potential roles of two risk metrics, individual and societal risk, to support decision making about new flood safety standards. These risk metrics are already used in the Dutch major hazards policy for the evaluation of risks to the public. Individual risk concerns the annual probability of death of a person. Societal risk concerns the probability of an event with many fatalities. Technical aspects of the use of individual and societal risk metrics in flood risk assessments as well as policy implications are discussed. Preliminary estimates of nationwide levels of societal risk are presented. Societal risk levels appear relatively high in the southwestern part of the country where densely populated dike rings are threatened by a combination of river and coastal floods. It was found that cumulation, the simultaneous flooding of multiple dike rings during a single flood event, has significant impact on the national level of societal risk. Options for the application of the individual and societal risk in the new flood safety policy are presented and discussed.     

Perceptions of Nuclear and Other Risks in Japan and the United States

As part of a study of nuclear power development in Japan and the United States, surveys of perceptions of risk toward 30 activities, substances, and technologies have been carried out in the Pacific Northwest and Tokyo, Japan. The results show that people in both countries have the highest level of dread toward nuclear waste disposal, nuclear accidents, and nuclear war, greater even than their dread of crime and AIDS. In addition to comparisons of dread, the paper also discusses similarities and differences between Japanese and American responses for other dimensions of risk perception.     

Domain Effects and Financial Risk Attitudes

We investigated whether financial risk preferences are dependent on the financial domain (i.e., the context) in which the risky choice options are presented. Previous studies have demonstrated that risk attitudes change when gambles are framed as gains, losses, or as insurance. Our study explores this directly by offering choices between identical gambles, framed in terms of seven financial domains. Three factors were extracted, explaining 68.6% of the variance: Factor 1 (Positive)—opportunity to win, pension provision, and job salary change; Factor 2 (Positive‐Complex)—investments and mortgage buying; Factor 3 (Negative)—possibility of loss and insurance. Inspection of the solution revealed context effects on risk perceptions across the seven scenarios. We also found that the commonly accepted assumption that women are more risk averse cannot be confirmed with the context structure suggested in this research; however, it is acknowledged that in the students’ population the variance across genders might be considerably less. These results suggest that our financial risk attitude measures may be tapping into a stable aspect of “context dependence” of relevance to real‐world decision making.