基于后悔规避的投资组合模型及其实证分析

由于人的情感、认知等因素对投资活动有直接影响,本文在投资活动中引入人的情感因素,提出了基于后悔规避的投资者效用函数,该效用函数是期末财富和预期财富的函数。建立了存在无风险资产时的最优投资组合模型,发现基于后悔规避投资组合模型的组合前沿存在两基金分离的现象。对我国上海股票市场进行了实证分析,得到了基于后悔规避投资组合模型的组合前沿,并验证了组合前沿存在两基金分离现象的结论。     

考虑基准资产的动态投资组合选取

职业基金经理的目标经常是希望自己的投资组合以稳定的表现能够超越所某一基准资产或组合。因此本文给出一个考虑基准资产的动态均值——方差投资组合选取模型。假设状态之间的转移遵循马氏过程,给定状态转移矩阵,可以得到对风险资产最优投入的解析表达式。此表达式表明对风险资产的投入由三项构成,前两项是不考虑基准资产时对风险资产的投入,最后一项与基准资产有关;在基准资产上的权重由基准资产收益的大小来决定,与积极投资组合管理者的风险厌恶程度无关;随着风险厌恶程度的增加,管理者会减少在风险资产上的投入。数值分析显示考虑基准资产的投资组合是一个积极的投资组合。     

Risk management,housing and stockholding

This article investigates the possible explanations of the stockholding puzzle by focusing on housing and other uninsurable risks (associated with income, health and business). Taking the French household wealth survey (Patrimoine 2004, French National Statistical Institute), we find that the share of financial wealth invested in stocks depends on transaction and information costs, risk aversion, exposure to real estate risk and, to a lesser extent, labour market risk. These results are obtained by controlling for endogenous home ownership status.     

Risk preference and indirect utility in portfolio-choice problems

We consider a portfolio-choice problem with one risky and one safe asset, where the utility function exhibits decreasing absolute risk aversion (DARA). We show that the indirect utility function of the portfolio-choice problem need not exhibit DARA. However, if the (optimal) marginal propensity to invest is positive for both assets, which is true when the utility function exhibits nondecreasing relative risk aversion, then the DARA property is carried over from the direct to the indirect utility function.     

Housing and relative risk aversion

This paper derives closed-form and numerical solutions for relative risk aversion in a standard consumption-based model enriched with housing. The presence of housing enables the household to hedge against unexpected shocks and may decrease relative risk aversion. In addition, housing may generate state-dependent, time-varying risk aversion.     

Why uncertainty matters: discounting under intertemporal risk aversion and ambiguity

Uncertainty has an almost negligible impact on project value in the standard economic model. I show that a comprehensive evaluation of uncertainty and uncertainty attitude changes this picture fundamentally. The illustration of this result relies on the discount rate, which is the crucial determinant in balancing immediate costs against future benefits, and the single most important determinant of optimal mitigation policies in the integrated assessment of climate change. First, the paper removes an implicit assumption of (intertemporal or intrinsic) risk neutrality from the standard economic model. Second, the paper introduces aversion to non-risk uncertainty (ambiguity). I show a close formal similarity between the model of intertemporal risk aversion, which is a reformulation of the widespread Epstein–Zin–Weil model, and a recent model of smooth ambiguity aversion. I merge the models, achieving a threefold disentanglement between risk aversion, ambiguity aversion, and the propensity to smooth consumption over time.     

Can Risk‐Averse Households Make Risky Investments? The Role of Trust in Others

In this paper, using data from the Survey on Health, Ageing and Retirement in Europe (SHARE, 2006 and 2013 waves), we illustrate the link between individuals’ attitudes to financial risk combined with their willingness to trust others, and their investments in risky assets. Individuals who display either risk tolerance alone or – to a lesser extent – risk aversion and trust more frequently decide to buy risky assets. The comparison between Scandinavian and Mediterranean countries indicates that trust plays qualitatively different roles depending on the prevailing combination of risk attitude and trust in the area being studied.     

Two-part tariffs set by a risk-averse monopolist

This paper revisits the classical issues of two-part tariffs by considering risk aversion of a monopolistic seller. Under demand uncertainty, equilibrium unit price declines and approaches towards marginal cost as the seller becomes more risk averse. Marginal-cost pricing prevails, irrespective of the seller’s risk attitude, if clients are homogenous. Under cost uncertainty, unit price is higher than marginal cost and monotonically increases in risk aversion. The model is then extended to accommodate buyers’ risk aversion and it is found that demand uncertainty makes unit price decline in the seller’s risk aversion again but increase in buyers’ risk aversion.     

Volatility spillovers and the global financial cycle across economies: Evidence from a global semi-structural model

The paper provides some evidence on the relevance of global uncertainty and risk aversion and the lesser importance of US interest rates for the global financial and business cycles. As framework, we use a global semi-structural model augmented with financial and trade interlinkages. Financial interlinkages are modelled with proposed global uncertainty, global risk aversion and global financial cycle channels. Trade interlinkages are modelled with proposed value-chain trade equations. We find that global uncertainty and global risk aversion are, by far, the main volatility factors in all economies. Other volatility factors such as US interest rates, foreign interest rates and trade-related factors rarely explain shares of forecast error variance above one percent.     

How to avoid the consequences of anticipated monetary policies

Summary. This paper analyzes how monetary policy in an overlapping generations model can be designed to avoid inflationary consequences of anticipated changes of monetary policies. Avoiding these inflationary consequences will require a once and for all increase (decrease) in monetary growth immediately before the policy switch takes place if the relative risk aversion is greater (less) than unity. If the relative risk aversion is greater than unity, the avoidance of inflationary consequences is also time-consistent. Moreover, a general monetary feedback rule ensures that the economy picks the steady state with the lowest inflation rate. Our results suggest that the difference between unanticipated and anticipated policy switches may not be as important as generally assumed, because the consequences of the latter can be neutralized. Received: September 19, 1995; revised version: July 27, 1998     

TESTING THE STRUCTURAL STABILITY OF A RISK AVERSION PARAMETER IN THE FOREIGN EXCHANGE MARKET*

This paper empirically investigates the structural stability of a risk aversion parameter in a model in which risk premia exist in forward foreign exchange. To maximize his or her lifetime utility, a representative investor invests in a riskless bond denominated in each major currency: dollar, DM and pound. We test the structural stability of the risk aversion parameter in Japanese data using Euler equations. The results show that the risk aversion parameter was invariant from 1973 to 1991.     

Asset pricing in a production economy with Chew–Dekel preferences

In this paper we provide a thorough characterization of the asset returns implied by a simple general equilibrium production economy with Chew–Dekel risk preferences and convex capital adjustment costs. When households display levels of disappointment aversion consistent with the experimental evidence, a version of the model parameterized to match the volatility of output and consumption growth generates unconditional expected asset returns and price of risk in line with the historical data. For the model with Epstein–Zin preferences to generate similar statistics, the relative risk aversion coefficient needs to be about 55, two orders of magnitude higher than the available estimates. We argue that this is not surprising, given the limited risk imposed on agents by a reasonably calibrated stochastic growth model.     

Monotone risk aversion

Summary. This paper defines decreasing absolute risk aversion in purely behavioral terms without any assumption of differentiability and shows that a strictly increasing and risk averse utility function with decreasing absolute risk aversion is necessarily differentiable with an absolutely continuous derivative. A risk averse utility function has decreasing absolute risk aversion if and only if it has a decreasing absolute risk aversion density, and if and only if the cumulative absolute risk aversion function is increasing and concave. This leads to a characterization of all such utility functions. Analogues of these results also hold for increasing absolute and for increasing and decreasing relative risk aversion.Received: 31 January 2003, Revised: 15 January 2004, JEL Classification Numbers: D81.The views, thoughts and opinions expressed in this paper are those of the author in his individual capacity and should not in any way be attributed to Morgan Stanley or to Lars Tyge Nielsen as a representative, officer, or employee of Morgan Stanley.     

The Risk and Incentives Trade-off in the Presence of Heterogeneous Managers

Agency theory predicts a negative relationship between risk and incentives, yet recent empirical evidence has not consistently found such a relationship. In fact, some researchers have found a positive relationship. By introducing competition for heterogeneous managers, who differ in their degrees of risk aversion, into a standard agency model, this paper demonstrates that a negative or positive relationship is theoretically possible. Which arises depends on the relative risk aversion parameters of the managers and the absolute and relative riskiness of the environments.Acknowledgement I thank two anonymous referees for helpful comments.     

Real estate and relative risk aversion with generalized recursive preferences

This paper investigates how real estate wealth affects the household’s attitude toward risk, and derives the closed-form expressions for risk aversion with generalized recursive preferences. We find three channels through which real estate wealth affects risk aversion, and these channels are absent in the traditional measure of relative risk aversion as in Arrow (1965) and Pratt (1964). First, illiquidity and fluctuations in real estate value increase consumption risk, thereby increasing risk aversion. Second, real estate as an asset provides a cushion for absorbing negative shocks to households, reducing risk aversion. Third, an increase in real estate prices lowers the profit of the firm that uses real estate as a factor of production, induces a decline in the real wage, and causes a rise in consumption risk. This channel increases risk aversion. We study how these channels as a whole determine relative risk aversion using a basic real business cycle model with generalized recursive preferences and compare the results with the case of expected utility preferences. Finally, we explore the implications of the firm’s and the household’s real estate holdings and illiquidity of real estate on the risk premiums for equity and real estate.     

An Experimental Study of Risk Aversion in Decision-making Under Uncertainty

This paper presents the findings of an experimental study of risk aversion in decision making under uncertainty. When presented with a series of gambles, subjects determined the certainty-equivalent wealth of each gamble. Risk aversion was measured by the Markowitz risk premium of the decision. The fixed effects regression model indicates the significant influence of the first three moments of a probability distribution in determining the risk premium. These results lend support to the rules of mean-variance and third-degree stochastic dominance. The extent of influence is also affected by the individual’s age, but not by gender, wealth or schooling.     

Risk Aversion and International Markets: Does Asset Trade Smooth Real Income?*

In a two-country model, complete asset markets do not guarantee that individuals will choose to eliminate all (diverifiable) risk in aggregate consumption. the presence of nontraded goods forces individuals to choose between reducing uncertainty in aggregate consumption and in the composition between traded and nontraded goods. This choice depends on a comparison of the standard coefficient of relative risk aversion with a second type of risk aversion that becomes relevant when nontraded goods are present, one that captures aversion to risk in composition. Regardless of the decision made, asset trade always reduces the risk premium.     

Risk and regret aversions on optimal bank interest margin under capital regulation

This paper examines the bank's optimal loan rate (and thus the bank's interest margin) under more stringent capital regulation when the bank is not only risk-averse but also regret-averse. Risk-averse preferences are characterized by an option-based utility function that includes disutility from the dislike of bank equity risk. Regret-averse preferences feature an option-based utility function that includes disutility from having chosen ex-post suboptimal alternatives. We show that an increase in bank capital requirement results in an increased margin under risk aversion dominating regret aversion, whereas it results in a reduced margin under regret aversion dominating risk aversion. The former holds when risk aversion domination stems from increasing risk-averse preference, but not from decreasing regret-averse preference, while the latter holds when regret aversion domination results from either decreasing risk-averse or increasing regret-averse preference. Risk aversion, as such, makes the bank more prudent and less prone to risk-taking, while regret aversion, as such, makes the bank less prudent and more prone to risk-taking.     

Experimental Estimates of Taxpayer Ethics

This paper extends the existing literature on taxpayer ethics in three ways. First, we construct a two-stage model of decision making, which allows us to disentangle risk preferences from ethical motivations for income tax compliance. Second, we develop a new experimental data set, which permits us to estimate the magnitudes of the relevant personality traits, risk aversion and morality, at the individual level. Third, we combine the experimental data with participant surveys so that ethical preferences are not only measured but also linked to demographic characteristics. We find that ethical preferences are correlated with risk aversion, age, gender, and marital status, among other characteristics.     

Growth and welfare effects of business cycles in economies with idiosyncratic human capital risk

This paper uses a tractable macroeconomic model with idiosyncratic human capital risk and incomplete markets to analyze the growth and welfare effects of business cycles. The analysis is based on the assumption that the elimination of business cycles eliminates the variation in idiosyncratic risk. The paper shows that a reduction in the variation in idiosyncratic risk decreases the ratio of physical to human capital and increases the total investment return and welfare. If the degree of risk aversion is less than or equal to one, then economic growth is enhanced. This paper also provides a quantitative assessment of the macroeconomic effects of business cycles based on a calibrated version of the model. Even for relatively small degrees of risk aversion (around one) the model implies that the elimination of business cycles has substantial effects on investment in physical and human capital, economic growth, and welfare.