Testing the Gaussian and Student's t copulas in a risk management framework

This paper introduces a semiparametric framework for selecting either a Gaussian or a Student's t copula in a d-dimensional setting. We compare the two models using four different approaches: (i) four goodness-of-fit graphical plots, (ii) a bootstrapped correlation matrix generated in each scenario with the empirical correlation matrix used as a benchmark, (iii) Value-at-Risk (VaR) and Expected Shortfall (ES) as risk measures, and (iv) co-Value-at-Risk (CoVaR) and Marginal Expected Shortfall (MES) as co-risk measures. We illustrate this four-step procedure using a portfolio of daily returns of six international stock indices. The VaR results confirm that the t-based copula model is an attractive alternative to the Gaussian. The ES analysis is less conclusive, and indicates that risk managers should jointly use the risk measure as well as the copula model. The results highlight the importance of promoting stress testing rather than ES in the risk management industry, particularly in the aftermath of a financial crisis.     

Using BS-PSD-LDA approach to measure operational risk of Chinese commercial banks

The research of operational risk management among Chinese commercial banks is still in its preliminary stage. Operational risk events are rare and data is hard to collect. This leads to very small data samples. Besides, a large number of empirical researches show that the distributions of operational losses are often skewed with fat tails. To address these issues, this paper puts forward a loss distribution approach (LDA) based on bootstrap sampling and piecewise-defined severity distribution (BS-PSD-LDA). The approach divides data samples into two distinct parts (high-frequency low-severity losses and low-frequency high-severity losses), and fits the two parts by lognormal distribution and Generalized Pareto distribution respectively. Using hand-collected samples of 426 operational losses in Chinese commercial banks during 1994–2010, we estimate the magnitude of operational losses using the BS-PSD-LDA method. We show that our method provides a better fit than the traditional parametric methods. Besides, the method using historical simulation of nonparametric method seems to offer a good fit to the sample as well. However, we believe that the BS-PSD-LDA approach offers improvement from the perspective of satisfying risk control requirement of the regulatory authority and ensuring the efficiency of funds' utilization.     

Mixed data sampling expectile regression with applications to measuring financial risk

To avoid information loss or measurement error in traditional methods dealing with mixed frequency data, we develop a novel mixed data sampling expectile regression (MIDAS-ER) model to measure financial risk. We construct the MIDAS-ER model by introducing a MIDAS structure into expectile regressions. This enables us to perform an expectile regression on raw mixed frequency data directly. We apply the proposed MIDAS-ER model to estimate two popular financial risk measures, namely, Value at Risk and Expected Shortfall, with both simulated data and four stock indices, and compare the model's performance with those of several popular models. The outstanding performance of our model demonstrates that high-frequency information helps to improve the accuracy of risk measurement. In addition, the numerical results also imply that our model can be a significant tool for risk-averse investors to control risk losses and for financial institutions to implement robust risk management.     

商业银行操作风险损失 计量路径与方法探讨

本文作者通过多年的摸索与实践,尝试对商业银行操作风险损失计量路径与方法提出新的研究思路,认为通过流程梳理识别操作风险,并以流程为基础按照银行八个业务条线和七类操作风险事件,运用计量统计学原理和风险管理理念,通过计量操作风险损失事件发生概率、操作风险事件导致的产品损失比率及在该流程上运行的产品价值得出业务流程的可预见损失。本文在以前研究的如何计量操作风险（损失）事件发生概率的路径和方法的基础上,就如何得到可预见损失的路径和方法进行综合阐述。这些方法突破了目前商业银行操作风险损失计量中的诸多困境,从商业银行操作风险管理实务角度分析具有较强的应用价值。     

商业银行操作风险的实证分析

近年来商业银行发生了事关操作风险的一系列大案、要案,逐步引起了人们对操作风险的重视。巴塞尔新资本协议把操作风险列为商业银行面临的三大风险之一,要求把它纳入到资本充足的计算框架内,各国学者和银行业也竭力加强对操作风险的研究和管理。操作风险的度量是操作风险管理的核心,度量方法可分为自上而下法和自下而上法。本文利用基于自上而下法建立的收入模型,使用2002年1季度至2011年1季度的季度数据对深圳发展银行和招商银行的操作风险进行了度量,与基本指标法模型所得结果进行了对比分析,并用两家银行的诉讼、仲裁数据进行了间接的实际验证。研究发现:收入模型比基本指标法模型能更准确的度量操作风险;两个银行的风险水平所占总风险比重符合国际惯例要求;招商银行的操作风险管理水平要高于深圳发展银行。     

开放视角下的国家综合负债风险与市场化分担

随着中国经济金融的日益开放,中国国家综合负债的规模与结构在动态变化:一方面,国家综合负债的某些旧因素(如银行不良资产)的存在形式发生了变化,另一方面,国家综合负债的一些新因素(社保基金缺口、巴塞尔协议的顺周期影响和汇率波动导致的外汇资产损失)开始显现。从开放视角考察,中国的国家综合负债风险形势仍较为严峻。在政府承担社会性支出的基础上,更多地重视和运用市场化分担方式是化解和防范国家综合负债风险的基本途径,保持经济持续稳定增长是应对国家综合负债风险的根本保障。     

Do Morning Classes Improve Student Learning of Microeconomics Principles?

This article analyzes the impact of class time on students’ grades by using data from Middle Tennessee State University. The data cover a period of six years and are based on a sample of 5803 individuals who enrolled in 133 sections of principles of microeconomics. To identify the causal impact of class time on students’ grades, I used a bootstrapping method which allowed assigning measures of accuracy to sample estimates. For males, the estimated coefficients were negative and statistically significant at the 10% level, and the coefficients suggested that a male student in an afternoon class could expect to earn a letter grade that is 0.029 points lower than he would have earned by taking the class in the morning. For females, the estimated coefficients were not statistically significant.     

Context matters

Eliciting the level of risk aversion of experimental subjects is of crucial concern to experimenters. In the literature there are a variety of methods used for such elicitation; the concern of the experiment reported in this paper is to compare them. The methods we investigate are the following: Holt–Laury price lists; pairwise choices, the Becker–DeGroot–Marschak method; allocation questions. Clearly their relative efficiency in measuring risk aversion depends upon the numbers of questions asked; but the method itself may well influence the estimated risk-aversion. While it is impossible to determine a ‘best’ method (as the truth is unknown) we can look at the differences between the different methods. We carried out an experiment in four parts, corresponding to the four different methods, with 96 subjects. In analysing the data our methodology involves fitting preference functionals; we use four, Expected Utility and Rank-Dependent Expected Utility, each combined with either a CRRA or a CARA utility function. Our results show that the inferred level of risk aversion is more sensitive to the elicitation method than to the assumed-true preference functional. Experimenters should worry most about context.     

农业高新技术投资项目风险评价

The agricultural high-teeh investment project （AHIP） is eharaeterized by technology-intensive, high risk and great profit. This article analyzes essential factors of the risks of the agricultural high-tech investment projects and the traditional risk evaluation method of agrtcultral projects. We think that the applications of the sensitivity, analysis and probability ore defer. Therefore; this article introduces a structural model to evaluate the risks of the agricultural high-tech investment projects and the system of the concrete evaluation indexes.     

How does issuing contingent convertible bonds improve bank's solvency? A Value-at-Risk and Expected Shortfall approach

This paper examines how issuing an innovative financial instrument called contingent convertible bond (CoCo) may enhance bank's solvency in comparison to issuing a conventional bond. CoCos convert automatically into common equity or have a principal write-down when bank's regulatory capital fails to meet a predetermined level. They have been invented and put into legislation with an objective to absorb losses thus preventing institutions from bankruptcy. From the standpoint of an issuer CoCos bring about two counter effects regarding his solvency: on one hand they recapitalize a bank approaching insolvency on the other hand CoCos pay much higher coupon comparing to conventional bonds. In our model a bank has two funding alternatives: either to issue CoCos or conventional bonds. We measure issuer's default risk using the concept of Value-at-Risk (VaR) and Expected Shortfall (ES). We conclude that CoCos have the potential to strengthen the resilience of the issuer on the condition that the probability of conversion triggering is higher than the VaR's significance level. Our findings can be helpful to the policymakers and banks to better understand the impact of CoCos on issuer's solvency.     

Precautionary principle as a rule of choice with optimism on windfall gains and pessimism on catastrophic losses

The paper investigates a decision-making process involving both risk and ambiguity. Differently from existing papers [Basili, M., Chateauneuf, A., Fontini, F., 2005. Choices under ambiguity with familiar and unfamiliar outcomes, Theory and Decision 58, 195-207; Chichilnisky, G., 2000. Axiomatic approach to choice under uncertainty with catastrophic risks. Resources and Energy Economics 22, 221-231; Chichilnisky, G., 2002. In: El-Shaarawi, A.,H., Piegorsch, W.W. (Eds.), Catastropic Risks. Encyclopedia of Environmetrics, vol. 1. John Wiley & Sons, Ltd, Chichester, UK, pp. 274-279], we assume that, in a Choquet Expected Utility framework, the decision-maker is pessimistic with respect to unfamiliar (catastrophic) losses, optimistic with respect to unfamiliar (windfall) gains and ambiguity-neutral with respect to the familiar world. A representation of the decision-maker's choice is obtained that mimics the Restricted Bayes-Hurwicz Criterion. In this way a characterization of the Precautionary Principle is introduced for decision-making processes under ambiguity with catastrophic losses and/or windfall gains.     

The Willingness to Accept Value of Statistical Life Relative to the Willingness to Pay Value: Evidence and Policy Implications

Large disparities between willingness to accept (WTA) and willingness to pay (WTP) based values of statistical life are commonly encountered in empirical studies. Standard economic theory suggests that if a public good is easily substitutable there should be no marked disparity between WTA and WTP values for the good, though the disparity increases with reduced substitutability. However, psychologists have shown that people often treat gains and losses asymmetrically and tend to require a substantially larger increase in wealth to compensate for a loss than the amount they would be willing to pay for an equivalent gain. Although most transport projects may aim to improve safety, situations arise when a relaxation of an existing regulation saves resources but increases the risk of death and injuries. A survey was recently carried out in New Zealand to determine people’s willingness to pay to reduce road risks and their willingness to accept compensation for an increase in risk. This paper reports the disparity observed between the two measures and considers some of the problems posed for policymakers.     

IDIOSYNCRATIC RISK,AGGREGATE RISK,AND THE WELFARE EFFECTS OF SOCIAL SECURITY

We ask whether a pay‐as‐you‐go financed social security system is welfare improving in an economy with idiosyncratic and aggregate risk. We show that the whole welfare benefit from insurance against both risks is greater than the sum of benefits from insurance against the isolated risks. One reason is the convexity of the welfare gain. The other reason is a direct risk interaction amplifying the utility losses from risk. Our quantitative evaluation shows that introducing a minimum pension leads to sizeable welfare gains, despite substantial crowding out. About 60% of these gains would be missing from summing up the isolated benefits.     

酒店行业人力资源风险分析及对策

在现有国内酒店人力资源管理的研究的基础上,主要分析了酒店行业人力资源存在的风险,主要包括了战略风险、日常运营风险、人力资源成本控制风险、人力资源合规性风险以及信息沟通风险,并提出了相应对策。     

Asset booms and fat tails in East Asia: Symmetric or asymmetric risks?

Do housing and equity booms significantly raise the probability at the margin of the realization of extreme outcomes in output and prices, and are the worst outcomes just as likely to occur as the good ones? This study addresses these questions for a group of eight East Asian countries. The risk of extreme outcomes occurring is measured by the probability of being in the tails of a distribution. The distributions of real output-and price level-gaps exhibit fat tails, in which the probability and size of the worst possible outcomes are higher than if the distribution were normal. Expected real output- and price level-losses from asset booms would therefore be larger than suggested by the normal distribution if asset price booms significantly raise the risk of extreme outcomes occurring. The main findings are that (i) asset price booms in housing and equity markets, but especially in housing, significantly raise the probability at the margin that real output- and price level-gaps will be in the tails of worst outcomes of their respective distributions and (ii) the risks arising from asset booms are not symmetric-only particularly bad outcomes are more likely. The implication for monetary policy is that an approach that is ex-ante more compatible with risk management may be appropriate.     

我国商业银行风险评价——基于年报数据的因子分析法

基于因子分析法以及商业银行年度报告中常用的经营指标作为风险因子来建立因子分析方程,并对商业银行风险进行评价,以及将评价结果与商业银行管理费用率进行回归后发现,两者之间存在明显的相关关系,商业银行风险评价得分越高,其风险水平就越低,其当年的管理费用率就越低,即商业银行风险管理水平对其当年的经营成本有直接影响。     

AVERTING AND INSURANCE DECISIONS IN THE WILDLAND–URBAN INTERFACE: IMPLICATIONS OF SURVEY AND EXPERIMENTAL DATA FOR WILDFIRE RISK REDUCTION POLICY

When confronted by catastrophic wildfire risk, homeowners simultaneously allocate resources between insurance and averting activities. Expected utility theory suggests that complete insurance coverage precludes investment in averting activities. However, when potential losses include a significant nonmarket component, optimal choice includes both. To investigate this issue, the authors analyze a unique combination of contingent valuation and experimental data. Both settings include a split-sample treatment to test the influence of wildfire risk zone information. The authors find that amenity values, subjective risk, averting efficacy perception, and demographic factors influence both willingness to pay and averting share and that risk information has the predicted ordering effect. (JEL C9 , Q51 , Q54 )     

Optimizing tracking error-constrained portfolios

Active portfolios subject to tracking error (TE) constraints are the typical setup for active managers tasked with outperforming a benchmark. The risk and return relationship of such constrained portfolios is described by an ellipse in traditional mean-variance space and the ellipse’s flat shape suggests an additional constraint which improves the performance of the active portfolio. Although subsequent work isolated and explored different portfolios subject to these constraints, absolute portfolio risk has been consistently ignored. A different restriction – maximization of the traditional Sharpe ratio on the constant TE frontier in absolute risk/return space – is added here to the existing constraint set, and a method to generate this portfolio is explained. The resultant portfolio has a lower volatility and higher return than the benchmark, it satisfies the TE constraint and the ratio of excess absolute return to risk is maximized (i.e. maximum Sharpe ratio in absolute space).     

我国垄断行业改革中的风险及控制——以航空运输业为例

垄断行业的改革是一项系统工程,涉及政府、行业、企业、公众等多个层面和主体,涉及众多外部约束条件和配套措施。我国航空运输业改革,不能简单地冠以市场化,也不能完全理解为放松规制,而必须把它作为一项系统工程来推进。在推进改革的进程中,需要妥善处理风险控制问题。我国航空运输业改革风险主要有操作层面风险、消费者利益受损风险、产业层面风险、体制政策风险和改革夹生风险等。因此,为确保改革顺利进行,应成立相对独立的综合机构,并建立相应的利益均衡博弈机制。     

A framework for estimating willingness-to-pay to avoid endogenous environmental risks

This paper proposes a general empirical strategy to estimate willingness-to-pay (WTP) for exogenous risk mitigation when environmental risks are endogenous in protective actions and consumers are imperfectly informed about the ambient risk levels. The strategy consists of a set of survey techniques and the dummy endogenous variable model (Heckman, 1978) to control for correlation in unobserved errors that enter the WTP equation and the protection-decision equation. The method is applied to the non-market valuation survey data on arsenic contamination in drinking water. Our results indicate that the estimated WTPs are significantly higher for households without self-protective action. Our approach thus offers not only the correct welfare estimate for exogenous reduction of environmental risks, but also yields policy implications qualitatively much different from the conventional approach. We also estimate the welfare value of the policy to inform and educate the public about the arsenic risk simultaneously with public risk mitigation. The estimated welfare value is similar to, though slightly higher than, that of risk mitigation without information component. This occurs due to the competing effects of information dissemination and risk mitigation efforts.