基于行为金融学的视角浅析固定收益证券市场的噪声现象

<正>一、引言Markowitz认为,市场上的投资者都是理性投资者,投资者可以分散投资来实现投资组合利益的最大化以及风险的最小化。Sharpe在此基础上提出了资本资产定价模型(CAPM),他将证券的风险分为两种,一种是非系统性风险,另一种是系统性风险,非系统性风险可以通过分散投资来消除,而系统性风险无法通过分散投资来消除。CAPM模型的具体形式是:     

证券投资组合的风险分散效应与应用研究

系统风险以及非系统风险是证券投资市场中普遍存在的两种风险形式,其中,采取证券投资组合方式可以有效的降低或控制非系统风险。在当今证券投资金融市场中,通过投资组合方式降低或分散风险的方式受到越来越的关注,应用范围也越来越广,特别是在基金投资领域。本文借助单指数模型对投资组合风险分散原理及应用进行分析,深入剖析证券风险,并阐述分散化投资应用的积极意义。     

资本资产定价模型在上海证券市场的有效性再检验

本文选定了2005年5月13至2012年6月8日期间的沪市作为研究对象,对资本资产定价模型（Capital Asset Pricing Model,CAPM）在沪市的有效性进行了时间序列检验及横截面检验,并得到结论：沪市股票收益与系统风险并不符合CAPM的预期,非系统风险对股票的收益起到重要的决定作用,CAPM对现阶段的沪市仍不适用。     

静态资本资产定价模型的有效性检验——基于Fama-Macbeth估计方法

本文利用36只深圳A股从1997年至2006年的月收益率数据,借助EXCEL软件,运用标准Fama-Macbeth估计方法来检验静态CAPM模型的有效性:以5年期的时间窗口进行时间序列回归,来估计CAPM模型的贝塔值;进行截面回归估计CAPM模型风险溢价和截距的平均值。并通过计算两个回归的值来判断静态CAPM模型对资产收益率波动的解释力。研究发现市场组合的超额收益率对个股、股票组合的超额收益率有较强的解释力;然而,CAPM模型的贝塔值对个股、股票组合的超额收益率的解释力均有限,但对股票组合的解释力要好于个股。     

现代资产组合理论的产生与发展综述

本文主要讨论现代资产组合理论的产生、发展与局限性。1952年Markowitz提出的均值一方差理论标志着现代资产组合理论的正式形成;进入20世纪60年代,以Sharpe、Lintner和Mossin为代表的一批学者,以Markowitz的均值一方差理论为基础,提出著名的资本资产定价模型(CAPM);作为CAPM的进一步推广,套利定价理论(ATP)显得更直观。现代资产组合理论尚存在理论假设过多、风险分散方式有限、风险判断机械、实际应用操作困难等方方面面的缺陷。     

我国开放式基金收益率与上证指数的相关性分析——以嘉实增长开放式基金为例

CAPM既是一个完整的理论模型,同时也是一个可以用于检验的实证模型,本文使用2011年初到2012年4月12日间共计308个交易日的数据构建CAPM,对我国开放式基金收益率变化与上证指数变化的相关性进行实证分析。对于任何资产而言,E(rm)和rf都是相同的,所以决定资产预期收益率的只有β,利用Eviews软件可以对实际数据的拟合效果进行检验。基于金融时间序列的参数检验方法认为,我国开放式基金的风险补偿系数(β)接近于1,代表了开放式基金对于市场组合的风险贡献度接近于1,即开放式基金的风险变化与市场组合的变化是同等程度的。     

我国开放式基金收益率与上证指数的相关性分析——以嘉实增长开放式基金为例

CAPM既是一个完整的理论模型,同时也是一个可以用于检验的实证模型,本文使用2011年初到2012年4月12日间共计308个交易日的数据构建CAPM,对我国开放式基金收益率变化与上证指数变化的相关性进行实证分析。对于任何资产而言,E(rm)和rf都是相同的,所以决定资产预期收益率的只有β,利用Eviews软件可以对实际数据的拟合效果进行检验。基于金融时间序列的参数检验方法认为,我国开放式基金的风险补偿系数(β)接近于1,代表了开放式基金对于市场组合的风险贡献度接近于1,即开放式基金的风险变化与市场组合的变化是同等程度的。     

酒店旅游行业股票长期贝塔系数的测算与预测

一、引言 自CAPM模型诞生以来,投资组合的贝塔系数估计在金融领域逐渐占有了重要的地位.CAPM阐述了在投资者都采用马科维茨的理论下进行投资管理的条件下市场均衡状态的形成,把资产的预期收益与预期风险之间的理论关系用一个简单的线性关系表达出来,即资产的预期收益率与风险的衡量尺度贝塔系数存在线性关系.     

基于小波分析的资本资产定价模型

小波分析是在应用数学的基础上发展起来的一门新兴学科,经过数十年来的飞速发展,小波分析理论已经被广泛运用于各行各业。本文在借鉴国内外关于小波分析理论在金融领域应用的基础上,将小波分析应用于资本资产定价模型(CAPM模型)中,从上证50指数中,挑选了其中5只股票,分析在不同时间尺度下,个股以及资产组合的市场风险。通过计算不同时间尺度下的β值,我们发现,对于个股以及资产组合,其系统性风险具有多期性结构。     

资产管理的金融产品创新之路

自从19世纪30年代格雷汉姆发表了经典的《证券分析》之后,美国专业的证券投资界基本上使用定性的基本面分析工具,并维持了传统主动型价值投资一统天下30多年的局面。直到1963年,WilliamSharpe发表了重要论文“投资组合的简单模型CAPM”,文中证明在传统的投资组合管理中,投资组合的回报来源于投资组合的市场风险回报贝塔（Beta即相对收益）和与市场无关的风险回报阿尔法（Alpha即绝对收益）,     

On the exclusion of assets from tests of the two-parameter model: A sensitivity analysis

This study investigates the sensitivity of tests of the CAPM to different sets of asset returns. Tests are conducted with market portfolios that include returns for bonds, real estate, and consumer durables in addition to common stocks. Even when stocks represent only 10% of the portfolio's value, inferences about the CAPM are virtually identical to those obtained with a stocks-only portfolio. In contrast, inferences are sensitive to the set of assets used in the tests.     

The Conditional CAPM and the Cross-Section of Expected Returns

Most empirical studies of the static CAPM assume that betas remain constant over time and that the return on the value-weighted portfolio of all stocks is a proxy for the return on aggregate wealth. The general consensus is that the static CAPM is unable to explain satisfactorily the cross-section of average returns on stocks. We assume that the CAPM holds in a conditional sense, i.e., betas and the market risk premium vary over time. We include the return on human capital when measuring the return on aggregate wealth. Our specification performs well in explaining the cross-section of average returns.     

Does It Pay to Bet Against Beta? On the Conditional Performance of the Beta Anomaly

Prior studies find that a strategy that buys high‐beta stocks and sells low‐beta stocks has a significantly negative unconditional capital asset pricing model (CAPM) alpha, such that it appears to pay to “bet against beta.” We show, however, that the conditional beta for the high‐minus‐low beta portfolio covaries negatively with the equity premium and positively with market volatility. As a result, the unconditional alpha is a downward‐biased estimate of the true alpha. We model the conditional market risk for beta‐sorted portfolios using instrumental variables methods and find that the conditional CAPM resolves the beta anomaly.     

The role of co-skewness in the pricing of real estate

The current study investigates whether systematic skewness offers an alternative perspective as to why the risk-adjusted returns on real estate should be similar to that for stocks. This is not a trivial issue since an affirmative finding implies that we might be incorrectly measuring real estate risk from both a pricing and a portfolio allocation perspective. A multivariate test of the Kraus-Litzenberger model is used to investigate this skewness proposition with the K-L CAPM tested against several alternative versions of the CAPM. The study finds that the Kraus-Litzenberger model offers additional insights into the measurement of real estate risk. Evidence is also found that both the zero beta and the consumption-oriented CAPM hold, which is consistent with the recent literature in real estate.     

Betting against sentiment? Seemingly unrelated anomalies and the low-risk effect

The negative CAPM alphas of high-beta and high-variance stocks are attributable to an unaccounted factor in the CAPM. We use eight seemingly unrelated anomalies to construct a composite factor in the spirit of the optimal orthogonal portfolio (FOP). Accounting for FOP re-establishes a positive relation between beta and average returns in time series regressions as well as cross-sectional and explains the negative alphas of high-beta and high-variance stocks. To analyze economic drivers behind FOP, we perform a horse race between leverage constraints, investor sentiment, and disagreement. Our results highlight investor sentiment as the most promising explanation for the low-risk effect.     

GOLBALIZATION, CORPORATE FINANCE, AND THE COST OF CAPITAL

International financial markets are progressively becoming one huge, integrated, global capital market—a development that is contributing to higher stock prices in developed as well as developing economies. For companies that are large and visible enough to attract global investors, having a global shareholder base means having a lower cost of capital and hence a greater equity value for two main reasons: First, because the risks of equity are shared among more investors with different portfolio exposures and hence a different “appetite” for bearing certain risks, equity market risk premiums should fall for all companies in countries with access to global markets. Although the largest reductions in cost of capital resulting from globalization will be experienced by companies in liberalizing economies that are gaining access to the global markets for the first time, risk premiums can also be expected to fall for firms in long-integrated markets as well. Second, when firms in countries with less-developed capital markets raise capital in the public markets of countries (like the U.S.) with highly developed markets, they get more than lower-cost capital; they also import at least aspects of the corporate governance systems that prevail in those markets. For companies accustomed to less-developed markets, raising capital overseas is likely to mean that more sophisticated investors, armed with more advanced technologies, will participate in monitoring their performance and management. And, in a virtuous cycle, more effective monitoring increases investor confidence in the future performance of those companies and so improves the terms on which they raise capital. Besides reducing market risk premiums and improving corporate governance, globalization also affects the systematic risk, or “beta,” of individual companies. In global markets, the beta of a firm's equity depends on how the stock contributes to the volatility not of the home market portfolio, but of the world market portfolio. For companies with access to global capital markets whose profitability is tied more closely to the local than to the global economy, use of the traditional Capital Asset Pricing Model (CAPM) will overstate the cost of capital because risks that are not diversifiable within a national economy can be diversified by holding a global portfolio. Thus, to reflect the new reality of a globally determined cost of capital, all companies with access to global markets should consider using a global CAPM that views a company as part of the global portfolio of stocks. In making this argument, the article reviews the growing body of academic studies that provide evidence of the predictive power of the global CAPM as well as the reduction in world risk premiums.     

New Paradigms in Stock Market Indexing

Considerable recent interest has been shown in a new set of stock‐market indices that are weighted by fundamental factors such as sales, earnings, dividends or book values, rather than by capitalization. In this paper, we analyze the performance of Fundamental Indexing? (“FI”). First, we show that the source of FI's recent excellent performance is not from its ability to systematically arbitrage mispricing in a noisy market but from increasing the portfolio's exposure to stocks with low price‐to‐book values and with small capitalizations. We find that FI does not produce a positive alpha when its excess returns are explained by the Fama‐French three‐factor model of CAPM beta, the value premium and the size premium. Second, we show that it is possible to construct a portfolio of exchange‐traded funds with similar factor loadings that can replicate, and sometimes, even outperform FI. However, we caution investors not to expect consistent outperformance from portfolios tilted towards value and small‐cap stocks. Historical data shows evidence of mean reversion in the performance of such strategies.     

Large returns,conditional correlation and portfolio diversification: a value-at-risk approach

This paper, using daily returns on 30 Dow Jones Industrial stocks for the period 1991-1999, investigates the possibility of portfolio diversification when there are negative large movements in the stock returns (i.e. when the market is bearish). We estimate the quantiles of stock return distributions using non-parametric and parametric methods that are widely being used in measuring value-at-risk (VaR). We find that the average conditional correlation of 30 stocks is much higher when the large movements are negative than that when the market is 'usual'. Further, we find that, contrary to the results of previous studies, there is no notable difference between the average conditional correlations when the large movements are positive and when the market is 'usual'. Moreover, it is evident from the results of the conditional CAPM that the portfolio's diversifiable and non-diversifiable risks, as measured by the error variance of the CAPM and beta respectively, are highly unstable when the market is bearish than that when it is 'usual' or bullish. The overall results suggest that the possibility of portfolio diversification would be eroded when the stock market is bearish. These findings have implications for portfolio diversification and risk management in particular and for finance in general. The ideas presented in this paper can be utilized for testing contagion in the international financial markets, a much-researched topic in international finance.     

Market proxies as factors in linear asset pricing models: Still living with the roll critique

A new model misspecification measure for linear asset pricing models is proposed for the case where misspecification maps to latency of one of the pricing factors; in this case, the market return. This measure is suited both for testing models that include the market return as a pricing factor in a traditional sense (i.e., whether the chosen model does or does not price a collection of risky assets) and ranking those models (i.e., determining which model performs best). The proposed measure is used in pricing portfolios reflecting the size, value, and momentum premia. The conditional CAPM of Jagannathan and Wang (1996) is found to best the performance of both the simple CAPM and the ICAPM of Petkova (2006). Moreover, it is discovered that winner stocks in a momentum portfolio may have higher market betas than loser stocks.