An equilibrium model of insider trading in continuous time

We study a Bayesian–Nash equilibrium model of insider trading in continuous time. The supply of the risky asset is assumed to be stochastic. This supply can be interpreted as noise from nonrational traders (noise traders). A rational informed investor (the insider) has private information on the growth rate of the dividend flow rewarded by the risky asset. She is risk averse and maximizes her inter-temporal utility rate over an infinite time-horizon. The market is cleared by a risk neutral market maker who sets the price of the risky asset competitively as the conditional present value of future dividends, given the information supplied by the dividend history and the cumulative order flow. Due to the presence of noise traders, the market demand does not fully reveal the insider’s private information, which slowly becomes incorporated in prices. An interesting result of the paper is that a nonstandard linear filtering procedure gives an a priori form for the equilibrium strategy to be postulated. We show the existence of a stationary linear equilibrium where the insider acts strategically by taking advantage of the camouflage provided by the noise which affects the market maker’s estimates on private information. In this equilibrium, we find that the insider’s returns on the stock are uncorrelated over long periods of time. Finally, we show that the instantaneous variance of the price under asymmetric information lies between the instantaneous variance of the price under complete and incomplete information. The converse inequalities hold true for the unconditional variance of the price.     

Dividend growth, stock valuation, and long-run risk

In this paper, we integrate the long-run concept of risk into the stock valuation process. We use the intertemporal consumption capital asset pricing model to demonstrate that a stock’s long-run dividend growth is negatively related to its current dividend-price ratio and positively related to its long-run covariance between dividends and consumption. Then, we show that the equilibrium price of a stock is determined by its current dividend, long-run dividend growth, and long-run risk. In all, our work suggests that risk cumulated over many periods represents an important parameter in assessing the theoretical value of a firm.     

Rational asset pricing bubbles and debt constraints

Rational price bubble arises when the price of an asset exceeds the asset’s fundamental value, that is, the present value of future dividend payments. The important result of Santos and Woodford (1997) says that price bubbles cannot exist in equilibrium in the standard dynamic asset pricing model with rational agents facing borrowing constraints as long as assets are in strictly positive supply and the present value of total future resources is finite. This paper explores the possibility of asset price bubbles under endogenous debt constraints induced by limited enforcement of debt repayment. Equilibria with endogenous debt constraints are prone to have infinite present value of total resources. We show that asset price bubbles are likely to exist in such equilibria. Further, we demonstrate that there always exist equilibria with price bubbles on assets in zero supply.     

Price-wage dynamics in a transition economy: The case of Poland

In this paper we analyse the wage-price relationship of an economy in transition characterized by important structural changes. It is known (see Perron, 1989) that structural breaks in stationary time series can induce apparent unit roots. The stationarity analysis of the series employed in the present model is conducted jointly with the assumption that the breakpoint location is unknown. We follow a testing procedure recently proposed by Zivot and Andrews (1992). Cointegration analysis of wages and prices in the presence of structural breaks finds empirical evidence in favour of two cointegrating vectors involving prices and wages. Our analysis focuses on the different structural behaviour of the price-wage dynamic relationship in the short and long term; we also demonstrate the relative importance of import prices as a source of wage-price fluctuations.     

On financial equilibrium with intermediation costs

This paper studies the set of competitive equilibria in financial economies with intermediation costs. We consider an arbitrary dividend structure, which includes options and equity with limited liabilities. We show a general existence result and upper-hemi continuity of the equilibrium correspondence. Finally, we prove that when intermediation costs approach zero, unbounded volume of asset trades is a necessary and sufficient condition, provided that, there is no financial equilibrium without intermediation costs.     

Arbitrage in stationary markets

We analyse questions of arbitrage in financial markets in which asset prices change in time as stationary stochastic processes. The main focus of the paper is on a model where the price vectors are independent and identically distributed. In the framework of this model, we find conditions that are necessary and sufficient for the absence of arbitrage opportunities. We discuss the relations between the results obtained and the phenomenon of “volatility-induced growth” in stationary markets. Financial support by the Swiss National Center of Competence in Research “Financial Valuation and Risk Management” (NCCR FINRISK) is gratefully acknowledged.     

Heterogeneous beliefs with herding behaviors and asset pricing in two goods world

We construct a incomplete information equilibrium model with heterogeneous beliefs and herding behaviors to identify their joint effects on the dynamics of asset prices. Herding behaviors make investors revise some of their estimations about expected growth rates of goods streams toward to the other one’s by a manner of weighted average of their own forecast and the other’s. As we expected, herding behaviors generate influences on the Radon Nikodym derivative, that is so-called “sentiment” as in Dumas et al. (2009), and in turn not only impact the dynamics of asset prices but also generate influences on investors’ survivals. We also show that introducing heterogeneous beliefs with herding behaviors permits to explain both the Backus–Smith puzzle and the mixed results about the influences of herding behaviors on asset prices. Moreover, we uncover that herding behaviors have positive influences on stocks’ risk premiums.     

带结构突变的确定趋势的单位根检验方法——兼对中国工农业产品比价的实证分析

存在未知结构突变点的DGP关于结构突变的信息是不完全的,理论上不可能得到媲美标准ADF检验或Perron检验的统计特性,且Perron检验比标准ADF检验更适合于作为其单位根统计量的极限分布。本文以Perron(2009)方法为基础,结合minSSR和FGLS详细讨论结构突变的单位根检验的三个步骤,澄清了很多模糊的认识。以我国工农业产品比价和工农业产品价格指数为例,本文的实证研究发现,中国工农业利益分配格局的重大改变是由国际经济事件造成的冲击引起的。     

Multifrequency jump-diffusions: An equilibrium approach

This paper proposes that equilibrium valuation is a powerful method to generate endogenous jumps in asset prices. We specify an economy with continuous consumption and dividend paths, in which endogenous price jumps originate from the market impact of regime-switches in the drifts and volatilities of fundamentals. We parsimoniously incorporate regimes of heterogeneous durations and verify that the persistence of a shock endogenously increases the magnitude of the induced price jump. As the number of frequencies driving fundamentals goes to infinity, the price process converges to a novel stochastic process, which we call a multifractal jump-diffusion.     

How beneficial was the Great Moderation after all?

This paper computes the welfare effect of the Great Moderation, using a representative-agent consumption-based asset pricing model. The Great Moderation is modeled according to the data properties of consumption and dividend growth rates, which display a reduction of their innovation-volatility and increased persistence: the latter is a characteristic that has been largely unaddressed in the literature. The theoretical model (a long-run risk model) is calibrated to match average asset pricing variables, as well as consumption and dividend dynamics before and during the Great Moderation. The model captures the relevant features of the Great Moderation (decreased variance, increased persistence, asset prices). It predicts only a modest welfare gain from Great Moderation (0.38 percent in consumption equivalent), due mainly to the utility cost of a late uncertainty resolution.     

Monetary policy,asset prices and consumption in China

This paper studies the wealth channel in China. Although the wealth channel has been found to be functioning in many advanced countries, its existence is yet to be explored in most emerging economies, also in China. In order to illuminate dynamics between monetary policy, asset prices and consumption, we use the structural vector autoregression method. The findings support the view that a loosening of China's monetary policy does indeed lead to higher asset prices. Furthermore, a positive shock to residential prices increases household consumption, while the role of stock prices seems to be small from the households’ point of view. Finally, we test the existence of the wealth channel more formally to find out whether those changes in asset prices that are caused by monetary policy are significant enough to increase consumption. In summary, the wealth channel remains weak but there are some signs of it via residential prices. The results are not that different from those attained for the advanced economies, where the size of the wealth channel has been found to be limited.     

Spurious Rejections by Perron Tests in the Presence of a Break

In this paper, we concentrate on the case of an exogeneously chosen break date, but entertain the possibility that an incorrect choice is made. In fact, the Perron test statistics considered are invariant to any break in the generating process at the assumed break date. Our results therefore apply equally to the case of a generating process with two breaks, only one of which is specifically accounted for in the analysis. As in Leybourne et al . (1998), we find that a neglected relatively early break can lead to spurious rejections of the unit root null hypothesis. Moreover, for all but one of the tests analyzed, spurious rejections now also arise if a true break occurs relatively soon after the assumed break date.     

Minimum-cost portfolio insurance

Minimum-cost portfolio insurance is an investment strategy that enables an investor to avoid losses while still capturing gains of a payoff of a portfolio at minimum cost. If derivative markets are complete, then holding a put option in conjunction with the reference portfolio provides minimum-cost insurance at arbitrary arbitrage-free security prices. We derive a characterization of incomplete derivative markets in which the minimum-cost portfolio insurance is independent of arbitrage-free security prices. Our characterization relies on the theory of lattice-subspaces. We establish that a necessary and sufficient condition for price-independent minimum-cost portfolio insurance is that the asset span is a lattice-subspace of the space of contingent claims. If the asset span is a lattice-subspace, then the minimum-cost portfolio insurance can be easily calculated as a portfolio that replicates the targeted payoff in a subset of states which is the same for every reference portfolio.     

The baby boom, the baby bust, and the housing market A second look

I re-examine Mankiw-Weil's (MW) claim that house prices will fall 47% by 2007. MW argue that the arrival of the Baby Boom generation at adulthood drove up prices during the 1970s. When the beginnings of the Baby Bust generation matured in the 1980s, prices softened. When this generation arrives in earnest, prices will collapse. I make three points: (1) The regression upon which MW hang their prediction has an implausible -8.1% trend, which drives their prediction. (2) Demand directly influences the rental price; the asset price (MW's variable) is influenced by demand only indirectly. I re-run MW's regression, replacing the asset price with the rental price, and their prediction disappears. (3) Relying on data presented by MW, I show that housing consumption rose during the 1970s, after adjusting for income growth. Just when MW say the asset price of housing was rising, consumers behaved as if the price were falling. Consumers were right: The rental price fell by approximately 20% during the 1970s.     

Asset pricing with loss aversion

The use of standard preferences for asset pricing has not been very successful in matching asset price characteristics, such as the risk-free interest rate, equity premium and the Sharpe ratio, to time series data. Behavioral finance has recently proposed more realistic preferences such as those with loss aversion. Research is starting to explore the implications of behaviorally founded preferences for asset price characteristics. Encouraged by some studies of Benartzi and Thaler [1995. Myopic loss aversion and the equity premium puzzle. The Quarterly Journal of Economics 110 (1), 73–92] and Barberis et al. [2001. Prospect theory and asset prices. Quarterly Journal of Economics CXVI (1), 1–53] we study asset pricing with loss aversion in a production economy. Here, we employ a stochastic growth model and use a stochastic version of a dynamic programming method with an adaptive grid scheme to compute the above mentioned asset price characteristics of a model with loss aversion in preferences. As our results show using loss aversion we get considerably better results than one usually obtains from pure consumption-based asset pricing models including the habit formation variant.     

The limit distribution of the estimates in cointegrated regression models with multiple structural changes

We study estimation and inference in cointegrated regression models with multiple structural changes allowing both stationary and integrated regressors. Both pure and partial structural change models are analyzed. We derive the consistency, rate of convergence and the limit distribution of the estimated break fractions. Our technical conditions are considerably less restrictive than those in Bai et al. [Bai, J., Lumsdaine, R.L., Stock, J.H., 1998. Testing for and dating breaks in multivariate time series. Review of Economic Studies 65, 395–432] who considered the single break case in a multi-equations system, and permit a wide class of practically relevant models. Our analysis is, however, restricted to a single equation framework. We show that if the coefficients of the integrated regressors are allowed to change, the estimated break fractions are asymptotically dependent so that confidence intervals need to be constructed jointly. If, however, only the intercept and/or the coefficients of the stationary regressors are allowed to change, the estimates of the break dates are asymptotically independent as in the stationary case analyzed by Bai and Perron [Bai, J., Perron, P., 1998. Estimating and testing linear models with multiple structural changes. Econometrica 66, 47–78]. We also show that our results remain valid, under very weak conditions, when the potential endogeneity of the non-stationary regressors is accounted for via an increasing sequence of leads and lags of their first-differences as additional regressors. Simulation evidence is presented to assess the adequacy of the asymptotic approximations in finite samples.     

Trends in international commodity prices: Panel unit root analysis

The purpose of this paper is to examine the behavior of international commodity prices within the context of the Prebisch–Singer hypothesis. To this end, I utilize a panel unit root approach which is able to account for multiple structural breaks and cross-section dependency. The unit root analysis for 24 international commodity prices during the period 1900–2003 shows evidence in favor of the trend stationary process in the commodity prices. The results thereby imply that shocks to commodity prices are temporary in nature and tend to be corrected over time. The estimation of the trend stationary models indicates that the Prebisch–Singer hypothesis is not a universal phenomenon.     

Long-run risk and hidden growth persistence

An extensive literature has analyzed the implications of hidden shifts in the dividend growth rate. However, corresponding research on learning about growth persistence is completely lacking. Hidden persistence is a novel way to introduce long-run risk into standard business-cycle models of asset prices because it tightly intertwines the cyclical and long-run frequencies. Hidden persistence magnifies endogenous changes in the forecast variance of the long-run dividend growth rate despite homoscedastic consumption innovations. Not only does changing forecast variance make discrimination between protracted spells of anemic growth and brief business recessions difficult, it also endogenously induces additional variation in asset price discounts due to the preference for early uncertainty resolution.     

Robustness for path-dependent volatility models

In this paper, we consider a generalisation of the Hobson–Rogers model proposed by Foschi and Pascucci (Decis Eocon Finance 31(1):1–20, 2008) for financial markets where the evolution of the prices of the assets depends not only on the current value but also on past values. Using differentiability of stochastic processes with respect to the initial condition, we analyse the robustness of such a model with respect to the so-called offset function, which generally depends on the entire past of the risky asset and is thus not fully observable. In doing this, we extend previous results of Blaka Hallulli and Vargiolu (2007) to contingent claims, which are globally Lipschitz with respect to the price of the underlying asset, and we improve the dependence of the necessary observation window on the maturity of the contingent claim, which now becomes of linear type, while in Blaka Hallulli and Vargiolu (2007), it was quadratic. Finally, in this framework, we give a characterisation of the stationarity assumption used in Blaka Hallulli and Vargiolu (2007), and prove that this model is stationary if and only if it is reduced to the original Hobson–Rogers model. We conclude by calibrating the model to the prices of two indexes using two different volatility shapes.