Risk Aversion,Downside Risk Aversion and Paying for Stochastic Improvements

This paper considers the relationship between risk preferences and the willingness to pay for stochastic improvements. We show that if the stochastic improvement satisfies a double-crossing condition, then a decision maker with utility v is willing to pay more than a decision maker with utility u, if v is both more risk averse and less downside risk averse than u. As the condition always holds in the case of self-protection, the result implies novel characterizations of individuals’ willingness to pay to reduce the probability of loss. By establishing a general result on the correspondence between an individual's willingness to pay, and his optimal purchase of stochastic improvement when there is a given relationship between stochastic improvements and the amount paid for them, we further show that all results on the willingness to pay can be applied directly to characterize the conditions under which a more risk averse individual will optimally choose to buy more stochastic improvement. Generalizations of existing results on optimal choice of self-protection can be obtained as corollaries.     

风险厌恶、失望厌恶和期货套期保值

本文考察失望厌恶对期货套期保值的影响。我们把一个不变的绝对风险厌恶（CARA）效用函数放进Gul（1991）的失望厌恶框架之内。它显示出，一个更厌恶失望的套期保值者会比一个厌恶失望程度较低的套期保值者选择一个更接近于最小方差套期保值的最优期货头寸。当套期保值者厌恶风险的程度较低时，失望厌恶的效应更强。对失望很小程度的厌恶会使一个接近于风险中性的套期保值者持有一个截然不同的头寸。此外，一个更厌恶风险或失望的套期保值者会有一个较低的参考点reference point。数字上的结果显示，厌恶失望的套期保值者的参考点往往会低于传统的厌恶损失的套期保值者的参考点。于是，厌恶失望的套期保值者的行动会更加保守，利用机会牟利的行为会少于传统的厌恶损失的套期保值者。     

Strong Increases in Downside Risk Aversion

A ranking of risk preferences is of economic interest insofar as it leads to unambiguous comparative statics predictions, and for this to be the case, the ranking must be a strict partial ordering. The ranking by greater risk aversion meets this demand at the second order, and yields a variety of well-known predictions concerning the effect of greater risk aversion on demands for insurance and risky assets, among many other applications. There has been less success at the third order, where ranking preferences by aversion to downside risk has not produced a strict partial ordering. The problem is that account has not been taken of the fact that an increase in downside risk aversion must induce changes in risk aversion as well. We propose a definition of stronger downside risk aversion that does yield a strict partial ordering by requiring a nested increase in both second- and third-order risk aversion, so that v is more strongly downside risk averse than u if v is more risk averse and more downside risk averse than u. We demonstrate that v being more strongly downside risk averse than u is characterized by v never liking any change in the probability distribution for y that induces a third-order stochastic dominance deterioration in the distribution for u(y). We apply the definition to obtain intuitive comparative statics predictions in the precautionary saving problem, and relate the definition to alternatives proposed in the literature.     

Risk Aversion and the Value of Risk to Life

The standard literature on the value of life relies on Yaari’s (1965) model, which includes an implicit assumption of risk neutrality with respect to life duration. To overpass this limitation, we extend the theory to a simple variety of preferences that are not necessarily additively separable. The enlargement we propose is relevant for the evaluation of life‐saving programs: current practice, we estimate, puts too little weight on mortality risk reduction of the young. Our correction exceeds in magnitude that introduced by the switch from the notion of number of lives saved to the notion of years of life saved.     

Implied Risk Aversion Parameter from Option Prices

This paper estimates the representative investor's coefficient of relative risk aversion using option price data. Estimation is carried out using the method of simulated moments. Employing the following assumptions: a) agents have constant proportional risk averse preferences, b) complete markets exist, and c) asset returns are distributed lognormally, an objective function is constructed within the equivalent martingale measure framework. Unlike the case of equity markets, the implied risk aversion parameter from option prices is quite low and stays between zero and one.     

State Dependence Can Explain the Risk Aversion Puzzle

Risk aversion functions extracted from observed stock and optionprices can be negative, as shown by Aït-Sahalia and Lo(2000), Journal of Econometrics 94: 9–51; and Jackwerth(2000), The Review of Financial Studies 13(2), 433–51.We rationalize this puzzle by a lack of conditioning on latentstate variables. Once properly conditioned, risk aversion functionsand pricing kernels are consistent with economic theory. Todifferentiate between the various theoretical explanations interms of heterogeneity of beliefs or preferences, market sentiment,state-dependent utility, or regimes in fundamentals, we calibrateseveral consumption-based asset pricing models to match theempirical pricing kernel and risk aversion functions at differentdates and over several years.     

Risk Aversion and the Bid–Ask Spread

This paper studies the properties of bid and ask prices posted by a monopolistic market maker, without parametric assumptions about the utility function of the market maker or about the probability distribution of the return of the risky asset. We first prove that the two prices can be higher or lower than the expected value of the asset, and that the spread is decreasing in the initial wealth when the market maker exhibits decreasing absolute risk aversion. We conclude by some examples illustrating the fact that almost all shapes can be obtained for the bid–ask spread (as a function of the inventory) depending on the probability distribution of the payment of the risky asset.     

证券监管中行政诉讼风险防范的法律思考

强化依法行政的意识，提高防范行政诉讼风险的能力，是近年来中国证券监管系统愈显紧迫的任务与课题。本文从司法受案和审理这一独特视角，结合证券监管实践，对几类可诉行政违法行为和相关疑难问题进行了深入探讨，廓清了理论和实践中存在的模糊认识，有针对性地提出了防范诉讼风险的有效对策。     

Risk Aversion, Transparency, and Market Performance

Using a model of market making with inventories based on Biais (1993), we find that investors obtain more favorable execution prices, and they hence invest more, when markets are fragmented. In our model, risk-averse dealers use less aggressive price strategies in more transparent markets (centralized) because quote dissemination alleviates uncertainty about the prices quoted by other dealers and, hence, reduces the need to compete aggressively for order flow. Further, we show that the move toward greater transparency (centralization) may have detrimental effects on liquidity and welfare.     

光票托收业务的风险及防范

光票托收是指银行(托收行)接受客户委托,将金融单据寄往境外代理行(代收行)委托收款的业务,是国际贸易与非贸易结算中经常使用的一种结算方式。由于这种托收不附带商业单据,仅仅是金融单据的托收,因此称为光票托收。光票托收业务操作简单,每笔涉及的金额一般都较小,风险容易被忽视。     

The Asian Financial Crisis and Investors’ Risk Aversion

This paper investigates whether changes in U.S. and Japanese banks’ risk aversion, measured by changes in the relative risk aversion (RRA) coefficient, are associated with the 1997 Asian financial crisis. It finds that an increase in U.S. banks’ risk aversion is unambiguously associated with the Asian crisis, while an increase in Japanese banks’ risk aversion is only weakly associated. The results suggest that, in addition to deteriorating fundamentals of the affected countries, investors’ (banks’) increased risk aversion appears to have reinforced observed capital outflows.     

Risk Aversion,Uncertain Information,and Market Efficiency

Abstract. We reexamine and extend tests of the uncertain information hypothesis (UIH) proposed by Brown, Harlow, and Tinic (1988, 1993). We find that their empirical results are sensitive to the sampling procedure employed and that their particular methodology does not sufficiently distinguish between event and nonevent periods. When the sampling procedure is modified to identify only relatively large, isolated events, the test results generally do not support the UIH. Instead, significant price shocks are consistently followed by short-lived price reversals. We observe this behavior following positive and negative events regardless of whether the event is classified as risk increasing or risk decreasing.     

First-Order Risk Aversion, Heterogeneity, and Asset Market Outcomes

We examine a wide range of two-date economies populated by heterogeneous agents with the most common forms of nonexpected utility preferences used in finance and macroeconomics. We demonstrate that the risk premium and the risk-free rate in these models are sensitive to ignoring heterogeneity. This follows because of endogenous withdrawal by nonexpected utility agents from the market for the risky asset. This finding is important precisely because these alternative preferences have frequently been proposed as possible resolutions to various asset pricing puzzles,  and  they have all been examined exclusively in a representative agent framework.     

Covered Purchasing Power Parity, Ex-ante PPP and Risk Aversion

The standard expectations augmented theory of ex-ante Purchasing Power Parity which was first developed by Roll assumes that agents are risk neutral. A Covered Purchasing Power Condition is developed which holds for the general case of risk aversion. A risk augmented form of ex-ante PPP is then derived using a consumption-based asset pricing framework. This is tested for the post-Bretton woods period for the group of seven main industrial countries. The results suggest that risk aversion has a part to play in explaining deviations from PPP.     

A Note on Risk Aversion,Prudence and Portfolio Insurance

This paper examines some properties of portfolio insurance that are linked to the risk aversion and the prudence of the investor. We provide explicit conditions to measure portfolio sensitivity to downside risk. We also characterize the degree of portfolio insurance by means of the ratio of absolute prudence to absolute risk aversion.     

浅谈信用证结汇方式下风险的规避(英文)

信用证曾是国际贸易中最安全的结算方式,由于其在实际操作中风险防范的难度,导致许多商人不愿再用。传统的信用证正在越来越多地被更安全更方便的信用证变形形式所取代。     

The Estimation of Systematic Risk under Differentiated Risk Aversion: A Mean-Extended Gini Approach

This paper examines a mean-Gini model of systematic risk estimation that resolves some econometric problems with mean-variance beta estimation and allows for heterogeneous risk aversion across investors. Using the mean-extended Gini (MEG) model, we estimate systematic risks for different degrees of risk aversion. MEG betas are shown to be instrumental variable estimators that provide econometric solutions to biases generated by the estimation of mean-variance (MV) betas. When security returns are not normally distributed, MEG betas are proved to differ from MV betas. We design an econometric test that assesses whether these differences are significant. As an application using daily returns, we estimate MEG and MV betas for U.S. securities.     

Compensation, Incentives, and the Duality of Risk Aversion and Riskiness

The common folklore that giving options to agents will make them more willing to take risks is false. In fact, no incentive schedule will make all expected utility maximizers more or less risk averse. This paper finds simple, intuitive, necessary and sufficient conditions under which incentive schedules make agents more or less risk averse. The paper uses these to examine the incentive effects of some common structures such as puts and calls, and it briefly explores the duality between a fee schedule that makes an agent more or less risk averse, and gambles that increase or decrease risk.     

A Model of Return Volatility with Application to Estimating Relative Risk Aversion

We estimate a monthly return volatility model that allows for the abrupt changes in volatility often observed in returns data. Using this model we are able to identify key months likely to correspond to draws from a high volatility regime. Using our model in conjunction with Merton's (1980) model relating expected risk premia to risk we obtain reasonable estimates of the coefficient of relative risk aversion.