An intertemporal capital asset pricing model with heterogeneous expectations

This paper extends the intertemporal capital asset pricing model (ICAPM) to integrate the heterogeneous trading behavior of three groups of investors; rational utility maximizers, positive feedback, or momentum, traders, and fundamental traders. Using several contemporary fundamental factors to proxy for the latter of these investors’ trading patterns, the interaction of these three groups of investors is explored in the G-7 markets using monthly stock market prices. There is no evidence that positive feedback traders are present in the sample data. Fundamental traders are however observable. This finding suggests that although positive feedback traders may drive stock prices in the short-run, as is typically observed in higher frequency data, fundamental traders likely play a role in pushing prices back to their fundamental value in the longer-run.     

A liquidity-based model for asset price bubbles

We provide a new liquidity-based model for financial asset price bubbles that explains bubble formation and bubble bursting. The martingale approach to modeling price bubbles assumes that the asset's market price process is exogenous and the fundamental price, the expected future cash flows under a martingale measure, is endogenous. In contrast, we define the asset's fundamental price process exogenously and asset price bubbles are endogenously determined by market trading activity. This enables us to generate a model that explains both bubble formation and bubble bursting. In our model, the quantity impact of trading activity on the fundamental price process—liquidity risk—is what generates price bubbles. We study the conditions under which asset price bubbles are consistent with no arbitrage opportunities and we relate our definition of the fundamental price process to the classical definition.     

基于ARMA模型的银行间质押式回购利率的实证研究

银行间质押式债券回购是目前我国货币市场交易最为活跃、成交金额最大的品种,其利率已经成为货币市场的代表性利率,同时也是我国短期金融产品定价的利率基准之一。本文试图寻找影响银行间债券市场回购利率的重要因素,并通过建立自回归移动平均模型,研究各种宏观经济与金融市场变量对该利率的影响。     

Is Mean-Variance Analysis Vacuous: Or was Beta Still Born?

We show in any economy trading options, with investors havingmean-variance preferences, that there are arbitrage opportunitiesresulting from negative prices for out of the money call options.The theoretical implication of this inconsistency is that mean-varianceanalysis is vacuous. The practical implications of this inconsistencyare investigated by developing an option pricing model for aCAPM type economy. It is observed that negative call pricesbegin to appear at strikes that are two standard deviationsout of the money. Such out-of-the money options often trade.For near money options, the CAPM option pricing model is shownto permit estimation of the mean return on the underlying asset,its volatility and the length of the planning horizon. The model is estimated on S&P 500 futures options data coveringthe period January 1992–September 1994. It is found thatthe mean rate of return though positive, is poorly identified.The estimates for the volatility are stable and average 11%,while those for the planning horizon average 0.95. The hypothesisthat the planning horizon is a year can not be rejected. Theone parameter Black–Scholes model also marginally outperformsthe three parameter CAPM model with average percentage errorsbeing respectively, 3.74% and 4.5%. This out performance ofthe Black–Scholes model is taken as evidence consistentwith the mean-variance analysis being vacuous in a practicalsense as well.     

Robust pricing and hedging under trading restrictions and the emergence of local martingale models

We pursue the robust approach to pricing and hedging in which no probability measure is fixed, but call or put options with different maturities and strikes can be traded initially at their market prices. We allow the inclusion of robust modelling assumptions by specifying a set of feasible paths on which (super)hedging arguments are required to work. In a discrete-time setup with no short selling, we characterise absence of arbitrage and show that if call options are traded, then the usual pricing–hedging duality is preserved. In contrast, if only put options are traded, a duality gap may appear. Embedding the results into a continuous-time framework, we show that the duality gap may be interpreted as a financial bubble and link it to strict local martingales. This provides an intrinsic justification of strict local martingales as models for financial bubbles arising from a combination of trading restrictions and current market prices.     

An evolutionary CAPM under heterogeneous beliefs

Heterogeneity and evolutionary behaviour of investors are two of the most important characteristics of financial markets. This paper incorporates the adaptive behaviour of agents with heterogeneous beliefs and establishes an evolutionary capital asset pricing model (ECAPM) within the mean-variance framework. We show that the rational behaviour of agents switching to better-performing trading strategies can cause large deviations of the market price from the fundamental value of one asset to spill over to other assets. Also, this spill-over effect is associated with high trading volumes and persistent volatility characterized by significantly decaying autocorrelations of, and positive correlation between, price volatility and trading volume.     

Risk premia,asset price bubbles,and monetary policy

We develop a dynamic general equilibrium asset pricing model with heterogeneous beliefs to study the effects of monetary policy on prices, risk premia, asset price bubbles, and financial stability. We propose a new framework for monetary policy with respect to bubbles. Because bubble risk premia arise from an interaction between disagreements among investors and dynamic trading constraints, under a non-accommodative monetary policy, liquidity adjusted risk and bubble risk premia increase. What matters for policy is the trading constrained fraction/mass of agents that disagree about fundamentals (i.e. optimists/pessimists). Accommodative policy can lead to a larger fraction of trading constrained agents that disagree, larger bubbles, and increased systemic risk. An implication of our results is that accommodative monetary policy in response to the Covid-19 crisis does not increase systemic risk due to asset price bubbles, as long as the policy keeps inflation under control.     

Alternative beta risk estimators and asset pricing tests in emerging markets: The case of Pakistan

This paper tests and compares the applicability of two asset pricing models specifically, the CAPM and the Fama–French three factor models for an emerging stock market namely, Pakistan. The paper analyses a number of beta risk estimators, including OLS, the Dimson thin trading estimator, a trade-to-trade estimator and a sample selectivity estimator. To uncover any possible influence of the return interval and the type of the market index, the analysis is carried out on three data frequencies namely daily, weekly and monthly as well as for a value and an equally weighted market index. The alternative beta estimators appear to correct thin trading bias but their effects on asset pricing tests are not visible. Moreover contrary to the expectations the test results for monthly and weekly frequencies are not promising. Instead for daily data the cross-section of returns are explained by a number of risk factors and trading volume.     

A note on fair value pricing of mutual funds

Mutual funds claim that they employ fair value pricing to prevent active investors from trading on their beliefs that the funds’ net asset values are stale. Our results support the funds’ assertions. We estimate the returns from the following active strategy: buy international open end mutual funds that do not employ fair value pricing on days that the S&P500 index rises by a large amount, and/or sell them on days that the S&P500 index declines by a large amount. These active strategies significantly outperform pure buy-and-hold strategies. We conclude that international mutual funds should make greater use of fair value pricing.     

MARGIN TRADING: A RISK-RETURN ANALYSIS

This paper attempts to present an integrated valuation analysis of investment options involving margin trading. The analysis is based on valuation theories such as Modigliani and Miller's capital structure model, the capital asset pricing model and the option pricing model. It is shown (i) that in margin trading, the return on equity is given by the return on investment plus a risk premium which increases proportionally with the margin-trading rate; (ii) that both the total risk (variance) and systematic risk (beta) of the return on equity increases proportionally with those associated with the return on investment; and (iii) that, when the option pricing model is applied to the case of margin trading, a more precise valuation formula can be employed.     

Financial crises in efficient markets: How fundamentalists fuel volatility

When a financial crisis breaks out, speculators typically get the blame whereas fundamentalists are presented as the safeguard against excessive volatility. This paper proposes an asset pricing model where two types of rational traders coexist: short-term speculators and long-term fundamentalists, both sharing the same information set. In this framework, excess volatility not only exists, but is actually fueled by fundamental trading. Consequently, efficient markets are more volatile with a few speculators than with many speculators. Regulators should therefore be aware that efforts to limit rational speculation might, surprisingly, end up increasing volatility.     

Limited investor attention,relative fundamental strength,and the cross-section of stock returns

We explore the underlying reasons for the apparent mispricing of firms based on fundamental information. We document that a relative fundamental strength strategy that buys (sells) firms with strong (weak) fundamentals is highly profitable for up to three years. The results cannot be explained by either price or earnings momentum, are robust to risk adjustments based on standard asset pricing models, and survive a battery of robustness tests. The strategy also works better among small firms, as well as firms with low analyst coverage and a high probability of informed trading. Our empirical findings support the hypotheses of limited investor attention and informed trading.     

Dynamic price discovery

This article analyzes the dynamic process of price discovery in a competitive securities market where investors are equally informed about the fundamental determinants of an asset's end-of-period value but, because they do not know each other's wealth positions, do not know the equilibrium price of shares at the start of a current trading session. Because a large number of participants is assumed, issues concerning market impact and market manipulation are avoided. As trading progresses, participants update their expectations of an asset's equilibrium value. As they do so, price can either converge to a new level or, following a run, revert back to a previous level. This implies that, in clusters of adjacent prices, price changes are more apt to be predominantly of like sign (positive or negative) than would be the case under random walk with a bid-ask spread. Moreover, reversals, when they do occur, should be larger than continuations. An examination of 1988 transactions data for the 30 Dow Jones Industrial stocks shows that this is indeed the case. With the effect of the bid-ask spread removed, first-order autocorrelation coefficients are found to be positive.     

The Efficiency of Net Asset Values for Asian–Country Mutual Funds in the US

The net asset values for Asian–country mutual funds in the US come from the underlying market's close a half–day earlier and create inefficiencies that improve returns 6 to 12 times in a pure sense. While these are mitigated because of loads, restrictions on trading and fair value pricing, informational biases exist in trading such funds. These can be exploited with a simple rule: If one plans to trade at all, then one should buy (sell) the fund after its own Asian–country index falls (rises). Basing NAVs on the underlying market's close after the NY market closes can eliminate this inefficiency.     

Relative asset price bubbles

In models of financial bubbles, the price of a stock is typically unbounded, and this plays a fundamental role in the analysis of finite horizon local martingale bubbles. It would seem that price bubbles do not apply to a priori bounded risky asset prices, such as bond prices. To avoid this limitation, to characterize, and to identify bond price mispricings consistent with an absence of arbitrage, we develop the concept of a relative asset price bubble. This notion uses a risky asset’s price as the numéraire instead of the money market account’s value. This change of numéraire generates some interesting mathematical complexities because many important numéraires, including risky bonds, can vanish with positive probability over the model’s horizon.     

Currency competition: A partial vindication of Hayek

This paper establishes the existence of equilibria for environments in which outside money is issued competitively. Such equilibria are typically believed not to exist because of a classic overissue problem: if money is valued in equilibrium, an issuer produces money until its value is driven to zero. By backward induction, money cannot have value in the first place. This paper shows that overissuance is not a problem if agents believe that if an issuer produces more than some threshold number of notes, then only those notes issued up to the threshold will be valued; additional notes will be worthless. This result is very general, applying to any monetary economy in which equilibria with and without valued money exist if the money supply is finite. The paper also compares the allocation achieved by a monopolist to that achieved with competitive issuance in both a search and an overlapping-generations environment. The results depend on the environment considered, but two general conclusions arise. First, it is ambiguous whether competitive issuers can achieve a more desirable allocation than a monopolist. Second, with competitive issuance, a licensing agency can always improve on pure laissez-faire and achieve the efficient allocation in the long run.     

The Valuation of Stock Purchase Rights as Call Options

The predictability of rights valuation models is tested, viewing the rights as call options. The results show that rights valuation models, on average, overprice the rights. The bias in the model prices of rights found in this paper is opposite to that predicted by Merton. Among several factors considered, possible volatility changes associated with raising capital through a rights offering account for some of the observed pricing deviation. A further regression analysis shows that while the pricing deviation is positively related to both the degree that the rights are in the money and the allocation ratio, it is negatively related to the time to expiration and the daily trading volume of the rights.     

The value of tradeability

This paper determines the value of asset tradeability in an option pricing framework. In our model, tradeability is valuable since it allows investors to exploit temporary mispricings of stocks. The model delivers several novel insights on the value of tradeability: The value of tradeability is the larger, the higher the pricing efficiency of the market is. Uncertainty increases the value of tradeability, no matter whether the uncertainty results from noise trading or from new information about the fundamental value of the stock. The value of tradeability is the larger, the longer the illiquid stock cannot be traded and the more trading dates the liquid stock offers.     

Understanding Housing Market Volatility

The Campbell–Shiller present value formula implies a factor structure for the price–rent ratio of housing market. Using a dynamic factor model, we decompose the price–rent ratios of 23 major housing markets into a national factor and independent local factors, and we link these factors to the economic fundamentals of the housing markets. We find that a large fraction of housing market volatility is local and that the national factor has become more important than local factors in driving housing market volatility since 1999, consistent with the findings in Del Negro and Otrok (2007). The local volatilities mostly are due to time variations of idiosyncratic housing market risk premia, not local growth. At the aggregate level, the growth and interest rate factors jointly account for less than half of the total variation in the price–rent ratio. The rest is due to the aggregate housing market risk premium and a pricing error. We find evidence that the pricing error is related to money illusion, especially at the onset of the recent housing market bubble. The rapid rise in housing prices prior to the 2008 financial crisis was accompanied by both a large increase in the pricing error and a large decrease in the housing market risk premium.