Margin requirements and equilibrium asset prices

This paper studies the effect of margin requirements on asset prices and trading volume in a general equilibrium asset pricing model where Epstein-Zin investors differ in their degree of risk aversion. Under the assumptions of unit intertemporal elasticity of substitution and zero net supply of riskless assets, I show analytically that binding margin requirements do not affect stock prices. This result stands in contrast to previous partial equilibrium analysis where fixed margin requirements increase the volatility of stock prices. In this framework, binding margin requirements induce a fall in the riskless rate, increase its volatility, and increase stock trading volume.     

Intergenerational risksharing and equilibrium asset prices

In the presence of overlapping generations, a social security system, with contingent taxes and benefits, can affect both asset prices and intergenerational risksharing. In a simple model with two risky factors of production—human capital, owned by the young, and physical capital, owned by all older generations—a social security system that optimally shares risks exposes future generations to a share of the risk in physical capital. Such a system reduces precautionary saving and increases the riskbearing capacity of the economy. Under plausible conditions it increases the riskless interest rate, and lowers the price and risk premium of physical capital.     

House prices and rents: An equilibrium asset pricing approach

We use a relatively general intertemporal asset pricing model where housing services and consumption are non-separable to measure overvaluation of housing in relation to rents in Spain, the UK and the US. Part of the increase in real house prices during the late nineties can be seen as a return to equilibrium following some undershooting after previous price peaks. However, marked increases in house prices led to price-to-rent ratios above equilibrium by mid-2003 (around 30% above equilibrium in the UK, 20% in Spain and 10% in the US). Part of that overvaluation — particularly in Spain and the UK — may be attributable to the sluggishness of supply in the presence of large demand shocks in this market and/or the slow adjustment of observed rents.     

A Markov model for valuing asset prices in a dynamic bargaining market

This paper proposes a Markov chain model for studying the impact on asset prices of illiquidity associated with search and bargaining in an economy. The economy consists of finitely many agents who can trade only when they find each other, and any trade between agents changes the population of the agent types which affects the asset price in the future. Assuming that the equilibrium utility as well as the trade price is proportional to the asset dividend, we obtain the asset prices in steady state. Through extensive numerical experiments, we observe that the equilibrium prices exhibit the cutoff phenomenon (i.e. crash) as the fraction of pessimistic agents becomes large. Models with a market maker as well as irrational agents are also considered.     

Inattention, wealth inequality and equilibrium asset prices

Heterogeneity in planning propensity affects wealth inequality and asset prices. This paper presents an economy where attentive agents plan their consumption period by period, while inattentive agents plan every other period. Inattentive consumers face more uncertainty and trade at unfavorable prices. If the only source of uncertainty is future income, inattentive consumers accumulate more wealth. In contrast, with uncertain asset returns inattentive investors accumulate less wealth. Asset prices must induce attentive consumers to voluntarily bear the burden of adjusting to aggregate shocks and, as a result, are much more volatile than in a representative agent model with full attention.     

The price of risk and ambiguity in an intertemporal general equilibrium model of asset prices

We consider a version of the intertemporal general equilibrium model of Cox et?al. (Econometrica 53:363–384, 1985) with a single production process and two correlated state variables. It is assumed that only one of them, Y ₂, has shocks correlated with those of the economy’s output rate and, simultaneously, that the representative agent is ambiguous about its stochastic process. This implies that changes in Y ₂ should be hedged and its uncertainty priced, with this price containing risk and ambiguity components. Ambiguity impacts asset pricing through two channels: the price of uncertainty associated with the ambiguous state variable, Y ₂, and the interest rate. With ambiguity, the equilibrium price of uncertainty associated with Y ₂ and the equilibrium interest rate can increase or decrease, depending on: (i) the correlations between the shocks in Y ₂ and those in the output rate and in the other state variable; (ii) the diffusion functions of the stochastic processes for Y ₂ and for the output rate; and (iii) the gradient of the value function with respect to Y ₂. As applications of our generic setting, we deduct the model of Longstaff and Schwartz (J Financ 47:1259–1282, 1992) for interest-rate-sensitive contingent claim pricing and the variance-risk price specification in the option pricing model of Heston (Rev Financ Stud 6:327–343, 1993). Additionally, it is obtained a variance-uncertainty price specification that can be used to obtain a closed-form solution for option pricing with ambiguity about stochastic variance.     

Disagreement and asset prices

How do differences of opinion affect asset prices? Do investors earn a risk premium when disagreement arises in the market? Despite their fundamental importance, these questions are among the most controversial issues in finance. In this paper, we use a novel data set that allows us to directly measure the level of disagreement among Wall Street mortgage dealers about prepayment speeds. We examine how disagreement evolves over time and study its effects on expected returns, return volatility, and trading volume in the mortgage-backed security market. We find that increased disagreement is associated with higher expected returns, higher return volatility, and larger trading volume. These results imply that there is a positive risk premium for disagreement in asset prices. We also show that volatility in and of itself does not lead to higher trading volume. Instead, only when disagreement arises in the market is higher uncertainty associated with more trading. Finally, we are able to distinguish empirically between two competing hypotheses regarding how information in markets gets incorporated into asset prices. We find that sophisticated investors appear to update their beliefs through a rational expectations mechanism when disagreement arises.     

金融资产危机与FM-IS-LM一般均衡模型

随着金融资产总量的迅速增长,金融资产价格变化对宏观经济的影响日益上升。本文在传统宏观经济理论的基础上,将可交易金融资产置入宏观经济模型之中,建立了FM-IS-LM一般均衡模型,并以此模型对金融资产膨胀、金融资产危机进行了系统化的讨论。这一研究的最重要价值在于把握金融资产膨胀、金融资产危机和实体经济波动的内在联系,提高宏观经济政策的完备性和有效性,避免金融危机在中国再现。     

Advisors and asset prices: A model of the origins of bubbles

We develop a model of asset price bubbles based on the communication process between advisors and investors. Advisors are well-intentioned and want to maximize the welfare of their advisees (like a parent treats a child). But only some advisors understand the new technology (the tech-savvies); others do not and can only make a downward-biased recommendation (the old-fogies). While smart investors recognize the heterogeneity in advisors, naive ones mistakenly take whatever is said at face value. Tech-savvies inflate their forecasts to signal that they are not old-fogies, since more accurate information about their type improves the welfare of investors in the future. A bubble arises for a wide range of parameters, and its size is maximized when there is a mix of smart and naive investors in the economy. Our model suggests an alternative source for stock over-valuation in addition to investor overreaction to news and sell-side bias.     

Fundamentals and bubbles in asset prices: Evidence from U.S. and Japanese asset prices

This paper investigates the existence and extent of non-fundamental bubbles in both U.S. and Japanese asset prices by employing a flexible empirical method which allows us to decompose asset prices into fundamental and non-fundamental bubble components. This study finds that a substantial fraction of U.S. and Japanese asset prices is accounted for by non-fundamental bubble components and that these asset prices overreact to non-fundamental bubble shocks. In addition, allowing for time-varying interest rates as another fundamental factor does not change any qualitative results about the role of non-fundamental bubble components. This suggests that the present value model fails to explain volatile asset price behavior even with time-varying interest rates. This paper was initially written when I was visiting Keio University in Japan. I benefited from several discussions with Mike Dothan, Pat Hess, and Steve LeRoy in my department, Takashi Kaneko, Yukitami Tsuji and Naoyuki Yoshino at Keio University, and Yong-Seok Park at the International University of Japan. Special thanks are due to the anonymous referee and the editor of this journal, who provided many useful and insightful comments that helped to improve the paper. This research was in part supported by a grant from the International Program Development.     

Single and joint default in a structural model with purely discontinuous asset prices

Structural models of credit risk are known to present both vanishing spreads at very short maturities and a poor spread fit over longer maturities. The former shortcoming, which is due to the diffusive behaviour assumed for asset values, can be circumvented by considering discontinuous asset prices. In this paper the authors resort to a pure jump process of the Variance-Gamma type. First the authors calibrate the corresponding Merton type structural model to single-name data for the DJ CDX.NA.IG and CDX.NA.HY components. By so doing, they show that it also circumvents the diffusive structural models difficulties over longer horizons. Particularly, it corrects for the underprediction of low-risk spreads and the overprediction of high-risk ones. Then the authors extend the model to joint default, resorting to a recent formulation of the VG multivariate model and without superimposing a copula choice. They fit default correlation for a sample of CDX.NA names, using equity correlation. The main advantage of our joint model, with respect to the existing non-diffusive ones, is that it allows full calibration without the equicorrelation assumption, but still in a parsimonious way. As an example of the default assessments which the calibrated model can provide, the authors price an FtD swap.     

A continuous time equilibrium model of forward prices and futures prices in a multigood economy

This paper is a theoretical investigation of equilibrium forward and futures prices. We construct a rational expectations model in continuous time of a multigood, identical consumer economy with constant stochastic returns to scale production. Using this model we find three main results. First, we find formulas for equilibrium forward, futures, discount bond, commodity bond and commodity option prices. Second, we show that a futures price is actually a forward price for the delivery of a random number of units of a good; the random number is the return earned from continuous reinvestment in instantaneously riskless bonds until maturity of the futures contract. Third, we find and interpret conditions under which normal backwardation or contango is found in forward or futures prices; these conditions reflect the usefulness of forward and futures contracts as consumption hedges.     

Risk and capital asset prices

This paper is an empirical examination of the statistical significance of the residual variance of individual assets as compared with the covariance of returns with various market portfolio proxies in predicting expected return. The data and analysis we present suggest that measures of covariance are no more significant than residual variance in predicting expected return. In this sense our paper is not supportive of the Sharpe-Lintner or Black versions of the capital asset pricing model.     

Time-varying risk aversion and asset prices

This paper uses a variant of the consumption-based representative agent model in Campbell and Cochrane [Campbell, J.Y., Cochrane, J.H., 1999. By force of habit: Consumption-based explanation of aggregate stock market behavior. Journal of Political Economy 107, 205–251] to study how investors’ time-varying risk aversion affects asset prices. First, we show that a countercyclical variation of risk aversion drives a procyclical conditional risk premium. Second, we show that with a small value for the volatility of the log surplus consumption ratio, a large value of risk aversion may not determine whether the equity premium and the risk-free rate puzzles can be resolved or not. Third, we show that countercyclical risk aversion may not help explain the predictability of long-horizon stock returns, the univariate mean-reversion of stock prices and the “leverage effect” in return volatility.     

Default risk premium and asset prices

We estimate a standard structural model of credit risk to draw insights about the premium demanded by investors for bearing default risk, using data on credit default swaps and market capitalization. We pin down the daily market value of assets for a set of non-financial firms and uncover cross-sectional heterogeneity in terms of the magnitude and time variation of the premium. By exploring the link between asset and default risk premia, we show that this heterogeneity closely depends on the relationship between the firm-specific market value of the assets and the business cycle.     

Consumption growth predictability and asset prices

We derive and test a consumption-based intertemporal asset pricing model in which an asset earns a risk premium if it performs poorly when expected future consumption growth deteriorates. The predictability of consumption growth combined with the recursive preference delivers news about future consumption growth an additional risk factor, in addition to news about current consumption growth. We model the consumption growth dynamics using a vector autoregressive (VAR) structure with a set of instrumental variables commonly used for forecasting future economic growth. Our VAR estimation provides strong empirical support for future consumption growth predictability. The cross-sectional test shows that the model explains reasonably well the dispersion in average excess returns of 25 portfolios sorted on size and book-to-market, as well as 25 portfolios sorted on size and long-term return reversal. Growth stocks and long-term winners underperform value stocks and long-term losers, respectively, because growth stocks and long-term winners hedge adverse changes in the future consumption growth opportunities.     

Exchange rate regimes and asset prices

We study the implications of alternative exchange rate regimes for asset prices in a portfolio balance model motivated by the recent US-China experience. We establish that asset price responses to various shocks differ across a flexible regime and a -unilateral- peg but the differences for most shocks tend to be rather small. Moreover, while both monetary and public debt expansions have inflationary effects on equity prices, the latter's impact is stronger under a flexible exchange rate regime. These two findings suggest that a flexible USD/rimni rate would not have limited the recent asset price inflation in the US.     

Hidden persistent disasters and asset prices

This study analyzes the effects of agents’ learning about hidden persistent economic disasters on asset prices. In this study, it is assumed that aggregate consumption follows a hidden Markov regime-switching process and a representative agent infers the current regime, normal regime, or disaster regime, sequentially from the realized path of the past consumption process. In this setting, the fluctuation in the agent’s posterior probabilities of the disaster regime augments the volatility of equity returns. By utilizing the stochastic differential utility, this study demonstrates that the current model can help resolve many asset pricing puzzles including the equity premium puzzle, equity volatility puzzle, and risk-free rate puzzle simultaneously. Further, the current model predicts the counter-cyclical pattern in the equity premium and equity-return volatility on the normal regime, although asset returns are negative and highly volatile during disasters. The study also demonstrates that, if the agent’s preferences are restricted to time-additive power utility, the consideration of hidden persistent disasters deepens the asset pricing puzzles.     

Global asset prices and FOMC announcements

This paper analyzes the impact of U.S. monetary policy announcement surprises on foreign equity indexes, short- and long-term interest rates, and exchange rates in 49 countries. We use two proxies for monetary policy surprises: the surprise change to the current target federal funds rate (target surprise) and the revision to the expected path of future monetary policy (path surprise). We find that different asset classes respond to different components of the monetary policy surprises. Global equity indexes respond mainly to the target surprise; exchange rates and long-term interest rates respond mainly to the path surprise; and short-term interest rates respond to both surprises. On average, a hypothetical surprise 25-basis-point cut in the federal funds target rate is associated with about a 1 percent increase in foreign equity indexes and a 5 basis point decline in foreign short-term interest rates. A surprise 25-basis-point downward revision in the expected path of future policy is associated with about a ½ percent decline in the exchange value of the dollar against foreign currencies and 5 and 8 basis point declines in short- and long-term interest rates, respectively. We also find that asset prices’ responses to FOMC announcements vary greatly across countries, and that these cross-country variations in the response are related to a country’s exchange rate regime. Equity indexes and interest rates in countries with a less flexible exchange rate regime respond more to U.S. monetary policy surprises. In addition, the cross-country variation in the equity market response is strongly related to the percentage of each country’s equity market capitalization owned by U.S. investors. This result suggests that investors’ asset holdings may play a role in transmitting monetary policy surprises across countries.