Intermarket efficiency: An application of interbattery APT to mortgage-backed securities

Increasing popularity of investments in mortgage-backed securities has led to closer integration of the mortgage market into traditional capital markets. Using monthly returns during 1982–1988 for common stocks, Treasury bonds and GNMA and FHLMC mortgage-backed securities, the interbattery factor analytic Arbitrage Pricing Theory of (Cho, 1984) is used to test five hypotheses for intramarket and intermarket integration. Results indicate that three to five common factors are found within the same security market, while only one to three factors are found common between different markets.The APT could not be rejected within the same security market, but was rejected in most intermarket comparisons. While risk-free rates are found to differ between markets, the risk premium tests are conclusive indicators of integration. Our results support claims that the stock, bond, and the mortgage-backed securities markets are integrated.     

Beta lives - some statistical perspectives on the capital asset pricing model

This note summarizes some technical issues relevant to the use of the idea of excess return in empirical modelling. We cover the case where the aim is to construct a measure of expected return on an asset and a model of the CAPM type is used. We review some of the problems and show examples where the basic CAPM may be used to develop other results which relate the expected returns on assets both to the expected return on the market and other factors.     

Pricing by hedging and no-arbitrage beyond semimartingales

We show that pricing a big class of relevant options by hedging and no-arbitrage can be extended beyond semimartingale models. To this end we construct a subclass of self-financing portfolios that contains hedges for these options, but does not contain arbitrage opportunities, even if the stock price process is a non-semimartingale of some special type. Moreover, we show that the option prices depend essentially only on a path property of the stock price process, viz. on the quadratic variation. We end the paper by giving no-arbitrage results even with stopping times for our model class.      

The numeraire portfolio: a new perspective on financial theory

The numeraire portfolio, also called the optimal growth portfolio, allows simple derivations of the main results of financial theory. The prices of self financing portfolios, when the optimal growth portfolio is the numeraire, are martingales in the ‘true’ (historical) probability. Given the dynamics of the traded securities, the composition of the numeraire portfolio as well as its value are easily computable. Among its numerous properties, the numeraire portfolio is instantaneously mean variance efficient. This key feature allows a simple derivation of standard continuous time CAPM, CCAPM, APT and contingent claim pricing. Moreover, since the Radon-Nikodym derivatives of the usual martingale measures are very simple functions of the numeraire portfolio, the latter provides a convenient link between the standard Capital Market Theory a la Merton and the probabilistic approach a la Harrison-Kreps-Pliska.     

Consistency among trading desks

We consider a bank having several trading desks, each of which trades a different class of contingent claims with each desk using a different model. We assume that the models are arbitrage-free. A practical question is whether a bank using several models can be arbitraged. Surprisingly it can happen that in some cases there must be an arbitrage. We discuss conditions under which the bank trades without offering arbitrage.The second-named author is grateful for support from NSERC Discovery grant 504316. An earlier version has been presented in the seminars at Fields Institute (2003), Cambridge University (2003) and IMA (2004); the authors thank for fruitful discussions. The authors also thank the referee for helpful comments.     

A Note: Natural Generalization of Black-Scholes in the Presence of Skewness,Using Stable Processes

The Lognormal price model is generalized to the class of Log-Stable Processes, a family which possesses self-similarity properties usually only associated with the Lognormal, but which, more generally, can model negatively skewed distributions of return. This generalization appears to explain several discrepancies between the Black-Scholes Model and observed market phenomena, such as the variation of implied volatility of option price with exercise price and term to expiry, and the nonzero probability of bankruptcy or ‘crash’. It will be argued that the class of maximally negatively skewed Stable distributions (a class which, paradoxically, contains the normal) may be utilized to produce models which imply these phenomena naturally.     

From T-Bills to Stocks: Seasonal Anomalies Revisited

This paper employed eleven data series which consist of stocks, bonds, bills, equity premiums, term premiums, and various default premiums to investigate whether January seasonality reported in existing literature is robust across different states of the economy as this has important trading implications. For the periods 1926–1990, small stocks, small stock premiums, low grade bonds, and default premiums (spread between high grade, low grade and government bonds) reveal January seasonality and that the seasonality is robust across different states of the economy except for low grade bond returns and default premiums. January seasonality for low grade bond returns and low grade bond default premiums are primarily driven by results found during periods of economic expansion. Overall, January seasonality is more evident during the economic expansion periods although the magnitude of default premiums is larger during periods of economic contraction. Furthermore, prior findings of strong summer equity returns are primarily driven by the results found during the periods of economic contraction. It is also found that equity returns are generally higher during periods of economic expansion.     

基于面板模型的中国国债风险溢价实证研究

该研究采用面板模型实证分析了2003年12月至2008年4月上海证券交易所债券市场国债风险溢价与利率期限结构及宏观经济变量的关系。实证结果显示,上期利率期限结构曲线越陡峭,当期国债风险溢价越高;上期通货膨胀水平越高,当期国债风险溢价越高,而再延长一期滞后期,会发现滞后第二期的通货膨胀水平与当期国债风险溢价存在显著负关系;货币供应同比增速增加时,国债风险溢价水平降低。     

商业银行监管资本套利的均衡分析

监管资本套利,产生于巴塞尔协议资本监管框架的缺陷,是一种利用资本监管制度之间的差异性以及制度内部的不协调性,运用某种手段在不改变实际风险水平的情况下提高资本充足率水平的行为。通过对以下问题的探讨:商业银行监管资本套利所获得的收益在银行与资金需求方之间的配置比例;针对某种资产的监管资本套利,对其他资产供求双方所产生的隐性套利收益的表现形式及其归属程度;由商业银行异质性所导致的监管套利顾客现象;信息不对称情况下,市场对于套利者与非套利者的逆向选择等等,认为银行监管部门应适当引导符合政策意图的套利行为,提高政策引导调控能力。     

Rare disaster risk and the expected equity risk premium

Consistent with the predictions of rare disaster models, we find that a proxy for the time‐varying probability of rare disasters helps to explain fluctuations in expectations of the equity risk premium. Our proxy for disaster risk is a recently developed measure of global political instability, and the expected market risk premium is from Value Line analysts' expected stock returns. Consistent with long‐run risk models, uncertainty about expected GDP growth and expected consumption growth is also significantly positively related to the expected market risk premium. We obtain similar results when we use the earnings–price ratio and the dividend–price ratio as proxies for the expected market risk premium.     

RISK, SEASONALITY AND THE ASYMMETRIC BEHAVIOUR OF STOCK RETURNS

For some time there has been a puzzle surrounding the seasonal behaviour of stock returns. This paper demonstrates that there is an asymmetric relationship between systematic risk and return across the different months of the year for both large and small firms. In the case of both large and small firms systematic risk appears to be priced in only two months of the year, January and April. During the other months no persistent relationship between systematic risk and return appears to exist. The paper also shows that when systematic risk is priced, the size of the systematic risk premium is higher for large firms than for small firms and varies significantly across the months of the year.     

国外有奖债券发行及借鉴思考

汶川地震后,用市场化手段建立巨灾融资体系的问题日益提上日程,文章通过对国外有奖债券的广泛搜集和整理,从政策和产品支持等方面介绍国外有奖债券发行的基本情况。并指出作为深受中小投资人欢迎,政府筹集中长期、低成本资金的重要融资工具,开发＂巨灾有奖债券＂,符合中央关于建立多层次巨灾融资体系的精神,有利于引导社会资金投入灾后重建。     

中国股票市场风险溢价研究

本文通过综合资产定价理论和实证文献研究结论,对1997年到2009年中国股市A股股票的风险溢价的截面差异作了详尽的实证研究。我们构造25个投资组合作为检验资产,进行Fama-MacBeth两步回归法,建立了基于市场风险溢价,账面市值比,盈利股价比,现金流股价比,投资资本比,工业增加值变化率以及回购利率和期限利差的八因素模型。我们的主要发现有以下三点:一是相对于Fama-French三因素模型,我们模型的实证解释力有显著提高;二是与过去的文献不同,我们发现回购利率和期限利差等债市指标对股市风险溢价的截面数据有显著解释能力;三是与基于投资的资产定价理论一致,我们发现投资比率和现金流股价比能显著反映我国股市的风险溢价。     

A股市场股权风险溢价的历史及启示

本文计算了1992～2000年、2001～2005年以及1992～2005年三个时间窗口下A股市场的股权风险溢价率；基于历史数据，就投资者所要求的股权风险溢价、通货膨胀与股权风险溢价的关系等问题进行了初步分析；相关分析也隐含了A股市场发展的政策建议。