基于双边风险厌恶及存在监督的委托-代理模型研究

研究了委托人与代理人双边风险厌恶及存在监督情形下的委托-代理问题.结论表明非对称信息下最优风险分担系数是委托人风险厌恶程度的递增函数,是代理人风险厌恶程度的递减函数,代理人努力水平是其风险厌恶程度的递减函数.监督措施的存在提高了对代理人的激励强度.     

后悔厌恶对商业银行存贷款定价的影响

存贷利差收入是银行主要的收入来源,存贷款定价问题是银行经营管理、风险控制的核心之一.在"代理商"模型的基础上,引入后悔系数和后悔效用函数,建立了基于双重厌恶银行的期望效用函数,并利用极值理论,确定了最优存贷款利差.双重厌恶期望效用函数反映了银行风险厌恶和后悔厌恶的双重特点,解决了现有研究忽略后悔情绪导致模型出现偏差的问题.从理论上分析了双重厌恶型银行最优的存贷款利差的决策问题,给出了其与市场风险、信用风险以及后悔情绪之间的关系.通过与纯风险厌恶型银行最优决策的对比发现,对于双重厌恶型银行来说,信用风险对存贷利差影响的弹性要小于纯风险厌恶型银行,而后悔厌恶程度越大其弹性就越小.由于后悔心理的存在减小了信用风险对存贷款利差影响的弹性.     

一类终端财富期望效用最大化问题: 通货膨胀情形

本文研究了一类受通货膨胀影响的终端财富期望效用最大化问题.对常数相对风险厌恶(CRRA) 情形的效用函数,用直接构造的方法得到了代理人的显式最优投资策略和最大期望效用,并给出其经济含义. 该思想来自线性二次最优控制问题中的完全平方技术.根据股票价格和通货膨胀率的历史数据,我们用SAS软件估计出模型中参数的近似值,并给出代理人的最优投资策略和最大期望效用.     

心理账户、损失厌恶与行为资产配置实证研究

基于前景理论和三参照点理论,建立了单心理账户和三心理账户下的线性损失厌恶行为投资组合模型,并利用中证基金指数数据构建了不同市场状态下的行为投资组合,实证研究不同损失厌恶系数、不同参照点、不同心理账户资金配置条件下模型的最优资产配置策略和投资组合绩效,研究发现线性损失厌恶模型更关注下侧损失,损失厌恶系数影响资产配置,注重安全性的投资者偏好低风险资产,而寻求实现抱负水平的投资者更偏好高收益资产。     

基于双边过度自信及风险厌恶的委托-代理问题研究

研究了委托人与代理人双边过度自信倾向及风险厌恶偏好情形下的委托-代理问题.结论表明最优风险分担水平随着委托人风险厌恶程度及代理人过度自信水平的增大而增加,随着代理人风险厌恶程度和委托人过度自信水平的减少而减少.最优努力水平随代理人风险厌恶程度及委托人过度自信水平的增大而提高,随委托人风险厌恶程度和代理人过度自信水平的减少而减少.     

基于非期望效用函数的投资决策研究

本文用数值分析的方法分析了在非期望效用函数下的投资决策问题.文章在模型和均衡分析的基础上指出,政府开支的增加,提高了代理人的风险投资,而政府税收的提高减少了风险投资.在数值分析中详细地分析了跨时替代弹性和相对风险厌恶系数彼此独立变化时,风险投资的变化情况,比较了风险投资受税收和风险的影响在非期望效用函数和期望效用函数下的差异,指出了期望效用函数对风险投资分析具有不确切性.     

基于预期的损失厌恶的“报童式”推理

利用Koszegi与Rabin的参照依赖效用函数对报童问题进行了研究,不仅求得基于预期的损失厌恶报童的最优订货量而且讨论了它的性质.研究发现,基于预期的损失厌恶的报童的订货量要低于利润最大化的报童的订货量,而且,基于预期的损失厌恶的报童的订货量随预期利润、损失厌恶程度的增加而减少.     

阶梯激励合约下代理人行为与合约激励效果

基于委托代理理论研究了阶梯激励合约下的代理人行为,并从委托人角度探讨了最优合约设计的问题。在一般市场需求分布和代理人效用函数下,代理人的效用可能是其努力水平的双峰函数,且存在一个阈值使得当合约绩效奖励超过该阈值时,代理人的努力水平“跳跃式”增加。通过比较阶梯激励合约与其他两类激励合约发现,当代理人是风险厌恶型且代理人的产出完全依赖于其努力水平,委托人总是更偏好阶梯激励合约。     

风险规避和最优套期保值比率

在一般的期望效用框架下,研究投资者的风险厌恶态度对于其套期保值策略的影响.首先,给出了投资者采用不同套期保值策略时,效用函数应该满足的条件;其次,讨论了期望效用框架下,Rubinstein整体风险厌恶度量与经典的Arrow Pratt局部风险厌恶度量和更强的Ross的风险度量之间的关系,提出了一组条件,使得在该组条件下,风险厌恶的人际间比较可以用Rubinstein整体风险厌恶度量来刻画;最后,在现货和期货服从正态分布的假设下,使用之前提出的条件,研究投资者风险厌恶程度对于其持有的最优套期保值比率的影响.     

幂效用函数的最优投资组合研究

本文对投资组合中较常用的风险厌恶型的幂效用函数进行研究。应用无差异曲线法求解出这种效用函数的最优投资比例,并对本文所得出的结论进行了实例应用分析。     

Background risk,bivariate risk attitudes,and optimal prevention

This paper extends Eeckhoudt et al.’s (2012) results for precautionary effort to bivariate utility function framework. We establish an equivalence between the agent’s precautionary effort motive and the signs of successive cross-derivatives of the bivariate utility function. We show that the introduction (or deterioration) of an independent background risk induces more prevention to protect against wealth loss provided the individual exhibits correlation aversion of some given order. The conditions on the individual’s risk preferences are given to generate some specific prevention behaviors in the univariate framework with multiplicative risks. Our conclusion also indicates that an increase in the correlation between wealth risk and background risk leads to a reduction in optimal prevention.     

模型不确定和极端事件冲击下带通胀的最优投资组合选择问题研究

本文研究了投资者在极端事件冲击下带通胀的最优投资组合选择问题, 其中投资者不仅对损失风险是厌恶的而且对模型不确定也是厌恶的. 投资者在风险资产和无风险资产中进行投资. 首先, 利用Ito公式推导考虑通胀的消费篮子价格动力学方程, 其次由通胀折现的终端财富预期效用最大化, 对含糊厌恶投资者的最优期望效用进行刻画. 利用动态规划原理, 建立最优消费和投资策略所满足的HJB方程. 再次, 利用市场分解的方法解出HJB方程, 获得投资者最优消费和投资策略的显式解. 最后, 通过数值模拟, 分析了含糊厌恶、风险厌恶、跳和通胀因素对投资者最优资产配置策略的影响.     

基于前景理论的建筑高危岗位人岗匹配冲突仿真研究

为了研究建筑高危岗位应聘人员的择岗特征,本文基于前景理论价值函数构建了人员风险岗位选择的元胞自动机模型进行仿真实验,而后对所得实验数据进行层次回归分析。结果表明,选择高危岗位的人员一般具有高估收益、低估事故损失和概率及低损失厌恶的心理特质,这与岗位要求相违背,即存在“高危人岗匹配悖论”;高基本工资、高安全激励和低风险补偿金的组合薪酬模式有助于高危岗位的人岗匹配;选聘对损失持续敏感的人员能有效降低安全风险;提高人员事故概率和损失预期、强化损失厌恶感知也有助于保障安全;针对人员择岗行为,损失厌恶与概率感知之间存在互补效应,而损失效用递减与损失厌恶、概率感知之间存在替代效应。     

Risk attitudes for nonlinear measurable utility

This paper concerns SSB utility theory in the monetary context. It introduces a measure of risk aversion and establishes necessary and sufficient conditions for comparative risk aversion. Nonseparable decompositions of an SSB utility function that have the form (x, y)=w(x)w(y)f(x–y) are examined. Risk properties such as constant risk aversion and a delta property are shown to give specific functional forms for an SSB utility function.     

Optimal insurance in the presence of insurer’s loss limit

In this paper we consider the optimal insurance problem when the insurer has a loss limit constraint. Under the assumptions that the insurance price depends only on the policy’s actuarial value, and the insured seeks to maximize the expected utility of his terminal wealth, we show that coverage above a deductible up to a cap is the optimal contract, and the relaxation of insurer’s loss limit will increase the insured’s expected utility.When the insurance price is given by the expected value principle, we show that a positive loading factor is a sufficient and necessary condition for the deductible to be positive. Moreover, with the expected value principle, we show that the optimal deductible derived in our model is not greater (lower) than that derived in Arrow’s model if the insured’s preference displays increasing (decreasing) absolute risk aversion. Therefore, when the insured has an IARA (DARA) utility function, compared to Arrow model, the insurance policy derived in our model provides more (less) coverage for small losses, and less coverage for large losses.Furthermore, we prove that the optimal insurance derived in our model is an inferior (normal) good for the insured with a DARA (IARA) utility function, consistent with the finding in the previous literature. Being inferior, the insurance can also be a Giffen good. Under the assumption that the insured’s initial wealth is greater than a certain level, we show that the insurance is not a Giffen good if the coefficient of the insured’s relative risk aversion is lower than 1.     

Exponential risk measure with application to UK asset allocation

In the paper the exponential risk measure of Damant and Satchell is used to formulate an investor's utility function and the properties of this function are investigated. The utility function is calibrated for a typical UK investor who would hold different proportions of equity. It is found that, for plausible parameter values, a typical UK investor will hold more equity under the assumption of non-normality of return if his utility function has the above formulation and not the standard mean-variance utility function. Furthermore, our utility function is consistent with positive skewness affection and kurtosis aversion. Some aggregate estimates of risk parameters are calculated for the typical UK investor. These do not seem well determined, raising issues of the roles of aggregation and wealth in this model.     

Archimedean copulas derived from utility functions

The inverse of the (additive) generator of an Archimedean copula is a strictly decreasing and convex function, while utility functions (applying to risk averse decision makers) are nondecreasing and concave. This provides a basis for deriving an inverse generator of an Archimedean copula from a utility function. If we derive the inverse of the generator from the utility function, there is a link between the magnitude of measures of risk attitude (like the very common Arrow–Pratt coefficient of absolute risk aversion) and the strength of dependence featured by the corresponding Archimedean copula. Some new copula families are derived, and their properties are discussed. A numerical example about modeling dependence of coupled lives is included.     

基于贝叶斯信息更新的风险规避库存策略研究

在贝叶斯库存控制研究中一个著名的结论是：当缺货需求不能被观测到时,最优贝叶斯库存水平总会高于短视策略库存水平,原因是决策者需要通过多订货来获取对需求分布的认识. 这是基于风险中性的研究,然后现实中决策者都期望规避风险. 基于贝叶斯信息更新研究了风险规避背景下需求部分可观测的多周期报童问题,决策者的周期内效用函数满足独立可加性公理. 通过引入非正规化概率,研究发现,对风险规避的决策者,当其效用函数具有不变绝对风险规避特征时,最优贝叶斯库存水平也会高于短视策略库存水平. 非正规化概率简化了动态规划方程与结果的证明.