Adverse effects of leverage and short-selling constraints in a financial market model with heterogeneous agents

This paper investigates the impact of leverage and short-selling constraints on financial market stability. Investors׳ demand is modelled in a well-known asset pricing model with heterogeneous beliefs. In particular, I generalise the heterogeneous agents model of Brock and Hommes (1998) and Anufriev and Tuinstra (2013) to allow for leverage constraints as well as a short-selling tax. I consider two examples of adaptive belief systems describing the coevolution of prices and investors׳ beliefs. First, if the market is inhabited by fundamentalist and chartist traders, demand constraints have potential adverse effects and may restrict the stabilising fundamentalist strategy such that mispricing and price volatility increase. Second, if the market is inhabited by fundamentalists, optimists and pessimists with fixed beliefs, demand constraints drive down price volatility, but mispricing remains. The results suggest the stabilising effects of demand constraints in financial markets are limited. Only if asset prices are too high compared to fundamentals, policy makers should consider constraining leverage ratios in order to deflate financial bubbles.     

The effects of dependent beliefs on endogenous leverage

The number of financial markets and the beliefs about the relation between markets can have large effects on the access to credit in a model with collateralized borrowing. In the model, investors have beliefs about the payout likelihoods for assets. I vary the degree of dependence between the likelihoods for the asset payouts and solve for the endogenous leverage ratios. When investors believe that the payouts of the assets are more dependent, the model predicts higher leverage ratios for all assets. When the number of financial markets available to investors increases, a condition in terms of the belief elasticity characterizes whether or not the leverage ratios increase.     

No arbitrage conditions and liquidity

We extend the fundamental theorem of asset pricing to the case of markets with liquidity risk. Our results generalize, when the probability space is finite, those obtained by Kabanov et al. [Kabanov, Y., Stricker, C., 2001. The Harrison-Pliska arbitrage pricing theorem under transaction costs. Journal of Mathematical Economics 35, 185–196; Kabanov, Y., Rásonyi, M., Stricker, C., 2002. No-arbitrage criteria for financial markets with efficient friction. Finance and Stochastics 6, 371–382; Kabanov, Y., Rásonyi, M., Stricker, C., 2003. On the closedness of sums of convex cones in L⁰$L^0$ and the robust no-arbitrage property. Finance and Stochastics] and by Schachermayer [Schachermayer, W., 2004. The fundamental theorem of asset pricing under poportional transaction costs in finite discrete time. Mathematical Finance 14 (1), 19–48] for markets with proportional transaction costs. More precisely, we restate the notions of consistent and strictly consistent price systems and prove their equivalence to corresponding no arbitrage conditions. We express these results in an analytical form in terms of the subdifferential of the so-called liquidation function. We conclude the paper with a hedging theorem.     

More hedging instruments may destabilize markets

This paper formalizes the idea that more hedging instruments may destabilize markets when traders have heterogeneous expectations and adapt their behavior according to performance-based reinforcement learning. In a simple asset pricing model with heterogeneous beliefs the introduction of additional Arrow securities may destabilize markets, and thus increase price volatility, and at the same time decrease average welfare. We also investigate whether a fully rational agent can employ additional hedging instruments to stabilize markets. It turns out that the answer depends on the composition of the population of non-rational traders and the information gathering costs for rationality.     

Existence of an equilibrium for infinite horizon economies with and without complete information

This work proves the existence of an equilibrium for an infinite horizon economy where trade takes place sequentially over time. There exist two types of agents: the first correctly anticipates all future contingent endogenous variables with complete information as in Radner [Radner, R. (1972). Existence of equilibrium of plans, prices and price expectations in a sequence of markets. Econometrica, 289–303] and the second has exogenous expectations about the future environment as in Grandmont [Grandmont, J. M. (1977). Temporary general equilibrium theory. Econometrica, 535–572] and information based on the current and past aggregate variables including those which are private knowledge. Agents with exogenous expectations may have inconsistent optimal plans but have predictive beliefs in the context of Blackwell and Dubbins [Blackwell, D., Dubins, L. (1962). Merging of opinions with increasing information. The Annals of Mathematical Statistics, 882–886] with probability transition rules based on all observed variables. We provide examples of this framework applied to models of differential information and environments exhibiting results of market selection and convergence of an equilibrium. The existence result can be used to conclude that, by adding the continuity assumption on the probability transition rules, we obtain the existence of an equilibrium for some models of differential information and incomplete markets.     

Asset price dynamics with heterogeneous beliefs and local network interactions

In this paper we investigate the effects of network topologies on asset price dynamics. We introduce network communications into a simple asset pricing model with heterogeneous beliefs. The agents may switch between several belief types according to their performance. The performance information is available to the agents only locally through their own experience and the experience of other agents directly connected to them. We model the communications with four commonly considered network topologies: a fully connected network, a regular lattice, a small world, and a random graph. The results show that the network topologies influence asset price dynamics in terms of the regions of stability, amplitudes of fluctuations and statistical properties.     

Bid-ask dynamic pricing in financial markets with transaction costs and liquidity risk

According to the classic no arbitrage theory of asset pricing, in a frictionless market a No Free Lunch dynamic price process associated with any essentially bounded asset is a martingale under an equivalent probability measure. However, real financial markets are not frictionless. We introduce an axiomatic approach of Time Consistent Pricing Procedure (TCPP), in a model free setting, to assign to every financial position a dynamic ask (resp. bid) price process. Taking into account both transaction costs and liquidity risk this leads to the convexity (resp. concavity) of the ask (resp. bid) price. We prove that the No Free Lunch condition for a TCPP is equivalent to the existence of an equivalent probability measure R that transforms a process between the bid price process and the ask price process of every financial instrument into a martingale. Furthermore we prove that the ask (resp. bid) price process associated with every financial instrument is then a R super-martingale (resp. R sub-martingale) which has a càdlàg version.     

Wavelet decomposition of heterogeneous investment horizon

Building on the assumptions that investors are heterogeneous and that not all of them are fully rational, the market for trading any financial instrument can be separated into several segments, each associated with a different investment horizon. Thus, the expected return on an asset for each horizon maintains a different functional relationship with an expected market return. In other words, the trading of an asset by investors with heterogeneous investment horizons results in the coexistence of multiple security market lines. This proposed theory, which offers an alternative interpretation of investment behavior from that of the capital asset pricing model (CAPM) and the efficient markets hypothesis (EMH), is verified by using the newly introduced amalgamated discrete wavelet transform.     

How money illusions and heterogeneous beliefs affect asset prices

We develop a dynamic asset pricing model with two investors with money illusions and heterogeneous beliefs about some aspects of the economy. The model is tractable and delivers closed forms for all equilibrium quantities. The study shows that money illusion leads the nominal shock risk to generate spillover effects on the real side of the economy and affects all equilibrium quantities, even without inflation disagreement. We find that bond yields increase, but the stock price decreases, as money illusion increases. Bond yield and stock price volatilities increase with fundamental disagreement, while the latter decreases with inflation disagreement. We also discover that the stock risk premium is inverse-U shaped as inflation disagreement increases. Moreover, we find that the optimistic investor holds positions in real bonds and stocks, and shorts the nominal bond to hedge against the risk of market changes, which is in line with the pessimistic investor’s beliefs.     

基于分数布朗运动和跳过程的股本权证定价模型

考虑到金融市场中资产价格具有的记忆性和长期相关性,模型假设股本权证标的资产价格服从分数布朗运动过程;并考虑到市场存在不确定因素而引起的价格巨大的波动,在模型中又引入了一个跳过程。首先得出权证定价的一般公式,最后在考虑股本权证行权后产生的稀释效应,得出稀释调整后的股本权证定价公式,并将其延伸到支付红利情况下。     

International endogenous growth,macro anomalies,and asset prices

This paper develops a two-country production economy with complete and frictionless financial markets and international trade in which investments in research and development (R&D) by entrants lead to endogenous new firm creation and economic growth. Innovative entrants use both consumption goods in their innovation technologies to capture international technological spillovers. Households also consume both goods. Specifically, I compare the equilibrium implications from the model with technology spillovers to the ones from an equivalent model without technology spillovers, i.e. a model where entrants only use domestic final goods in their R&D expenditures. With these two models at hand, new insights on the interplay of endogenous growth and long-run risks, technology spillovers, complete financial markets, and international trade are obtained, particularly with respect to international macro and asset pricing anomalies. The novel technology spillover channel has the potential to help explaining a number of these anomalies.     

Empirical evidence of conditional asset pricing in the Indian stock market

Studies of various alternative empirical asset pricing models have mostly concentrated on developed markets. However, despite the importance of this issue, surprisingly little is known about how different asset pricing models behave in emerging capital markets. The purpose of this paper is to determine the suitability of conditional compared to unconditional versions namely, the capital asset pricing model and the Fama-French three-factor model for the Indian stock market. The key distinction between the present empirical tests and previous tests is the application of the Kalman filter method for dynamic beta estimation in the Indian market. The findings indicate that the cross-sectional variation in expected returns is driven by mainly two firm characteristics size and book-to-market ratio.Unlike the unconditional model, the market beta is able to capture the variation of expected return in conditional model. The results imply that information has a role and investors use the prior belief and macroeconomic variables as predictive variables to determine the cost of capital. These results are supported by some recent findings that Fama-French three-factor model is the only multifactor model that consistently sources three different types of risk included in the list of anomalies.     

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.     

A Bayesian approach to excess volatility,short-term underreaction and long-term overreaction during financial crises

In this paper, we introduce a new Bayesian approach to explain some market anomalies during financial crises and subsequent recovery. We assume that the earnings shock of an asset follows a random walk model with and without drift to incorporate the impact of financial crises. We further assume the earning shock follows an exponential family distribution to accommodate symmetric as well as asymmetric information. By using this model setting, we develop some properties on the expected earnings shock and its volatility, and establish properties of investor behavior on the stock price and its volatility during financial crises and the subsequent recovery. Thereafter, we develop properties to explain excess volatility, short-term underreaction, long-term overreaction, and their magnitude effects during financial crises and the subsequent recovery. We also explain why behavioral finance theory could be used to explain many of the asset pricing anomalies, but traditional asset pricing models cannot achieve this aim.     

价值分析者和技术分析者交互作用下的股市价格波动

运用市场上常用的基本价值分析策略和技术分析策略,以适应性信念系统模型为基础,构建了一个非线性演化的价格动力学模型。依此模型模拟的结果表明:基本价值分析策略和技术分析策略的交互行为产生波动集聚现象,适应性信念模型模拟的结果与我国股市实际的数据相似。     

Optimality conditions¶and bubbles in sequential economies¶and bounded relative risk-aversion

We provide specific qualifications in order that Kuhn–Tucker type Euler equations and transversality conditions at infinity hold in stochastic equilibrium models with heterogeneous agents and where assets are traded in sequential markets. It is not assumed that uncertainty is modeled as an event-tree structure or that preferences are necessarily bounded. We also describe an important class of preferences based on bounded relative risk aversion which yields relevant simplifications. Our results are used to establish conditions that rule out asset pricing bubbles. Specific examples of economies with bubbles are also discussed. Received: 28 January 2002 / Accepted: 19 July 2002 We are grateful to the editor and an anonymous referee for their valuable comments. This research was partially supported by MURST (Italy), National Group on “Nonlinear Dynamics and Stochastic Models in Economics and Finance”.     

Market perception of sovereign credit risk in the euro area during the financial crisis

We study market perception of sovereign credit risk in the euro area during the financial crisis. In our analysis we use a parsimonious CDS pricing model to estimate the probability of default (PD) and the loss given default (LGD) as perceived by financial markets. In our empirical results the estimated LGDs perceived by financial markets stay comfortably below 40% in most of the samples. Global financial indicators are positively and strongly correlated with the market perception of sovereign credit risk; whilst macroeconomic and institutional developments were at best only weakly correlated with the market perception of sovereign credit risk.     

Does financial integration affect real exchange rate volatility and cross-country equity market returns correlation?

Existing empirical studies show that financial integration affects the behavior of average excess returns, cross-country equity market returns (EMR) correlations and real exchange rate (RER) volatility. We employ a recently developed two-country model with recursive preferences, frictionless and complete markets and highly correlated long-run innovations to examine whether full financial integration (i.e. full risk-sharing) affects the US-Canada EMR correlation and the US RER volatility, consistently with existing empirical findings. First, full risk-sharing gives rise to a relatively high RER volatility. Second, it induces very strong positive cross-country EMR correlations. Both quantities are higher than those observed in the US-Canada asset pricing data, and increase as the risk-sharing incentive increases. In contrast, “international consumption quantities” are weakly sensitive to changes in the level of aversion to consumption and utility risk.     

不完全资本市场与国际贸易赤字

本文通过带有风险资产的两期一般均衡模型研究了不完全资本市场和一国国际贸易之间的相关性。研究表明,当市场是完全的或者没有风险资产时,一国的国际贸易是平衡的,但是当资本市场不完全时会出现贸易不平衡。如果是国家间的不完全市场,由于一些国家的收入对风险资产的回报具有更强的相关性,使得国家间的贸易出现不平衡;如果资产在一个国家内是不完全的,则由于完全市场国家具有更强的国内分散收入变化风险的能力,会减少预防性储蓄,导致更大的贸易赤字。一些国际数据基本支持本文的研究结论。     

Asset pricing for inefficient markets: Evidence from China and India

Over last four decades, evidence of market inefficiencies has been widely documented by several scholars for all major stock markets in the globe. Chinese and Indian markets are not exempt. Inefficiencies in these markets are described by many authors as roots of all mispricing. Mispricing might be the outcome of application of familiar asset pricing models which may mislead an investor into adopting inappropriate policies for his new investments or for reallocating his old investments. In an alternative approach, we propose a transformation on original market returns in the objective of relaxing the strong assumption of market efficiency behind application of an asset pricing model. This modification will widen the scope of rational models on asset pricing ranging from an efficient to an inefficient market.