On non-ergodic asset prices

We investigate the asset prices dynamics and the long-run market shares of two competing financial mediators who are selected by consumers. We demonstrate that the social interaction among consumers constitutes an endogenous path-depending source of risk in a financial market. Depending on consumers’ evaluation of the mediator’s investment, asset prices may behave in a non-ergodic manner: the price process converges in distribution but the limiting distribution is not necessarily uniquely determined, its multiplicity being characterized by the multiplicity of possible long-run market shares. The convergence of the process is sensitive to initial conditions and depends on the history of noise-trader transactions. Long-run portfolio holdings may be in-efficient since investors holding mean-variance efficient portfolios may not be identified.     

Tests of the CAPM under structural changes

Abstract

In accordance with the empirical regularity of time-varying betas we estimate and test for the Sharpe–Lintner CAPM by allowing for structural change(s) in betas. Empirical applications using BM- and size-sorted decile portfolios suggest the following interesting results. Firstly, there exists at least one break for all the portfolios under consideration. Secondly, the estimated break dates are quite similar for some of the portfolios, indicating the possible existence of a common break using multivariate time series. Finally, we find the CAPM can be consistent with the data in some regimes but may appear to be inconsistent with the data in some other regimes. This particularly appealing feature has been completely ruled out under the conventional single-equation framework.     

The Idiosyncratic Risk-Return Relation: A Quantile Regression Approach Based on the Prospect Theory

Given some debate on the empirical idiosyncratic risk-return relation in the literature, we reexamine the relation using a quantile regression approach based on the prospect theory developed by Kahneman and Tversky [1979]. The quantile regression approach allows the coefficient on the independent variable (idiosyncratic risk) to vary across the distribution of the dependent variable (return). Our sample consists of stocks traded on the NYSE, AMEX, and NASDAQ during 1980–2010: 80,324 firm-year observations and 8,123 firms in total. The quantile regression results show that idiosyncratic risk is positively (negatively) related to returns at the high (low) quantiles of returns. The findings are consistent with the prospect theory that investors have a tendency to be less (more) willing to gamble with profits (losses). The results also demonstrate that the least-squares and least-sum optimization methods commonly used in prior research do not capture the relations between idiosyncratic risk and returns at the tail parts of the distribution of returns. Therefore, our empirical results provide new insights into the idiosyncratic risk-return relation in the literature.     

金融危机背景下银行类股票β值及其稳定性的实证检验

在金融研究中,风险和收益、个股与整个股市的波动一直是人们最为关注的问题。特别是在2007年8月美国次贷危机迅速蔓延后,各个公司更加重视股市波动的研究,以求最大限度地规避风险、获得最大收益。在金融研究中,人们通常用期望值表示收益,用方差和标准差来衡量风险。而在两者的关系研究中,资本资产定价模型反映了均衡状态下单个证券的预期回报与其相对市场风险值之间的关系,也描述了证券的风险溢价与市场组合风险溢价之间的关系。选择金融危机迅速传播后的2007年8月到2011年10月21日为研究时间段,选择上海证券交易所A股市场的浦发银行（600000）等14只银行类股票为研究对象,确定它们的值,研究银行类股票与整个股市波动的相关性,说明它们的风险溢价与市场组合风险溢价之间的变动关系。考虑到在所选时间段中,2010年3月开展的融资融券业务可能会对股票值的稳定性有所影响,因此,在求出这些股票的值后,还对这些股票值的稳定性进行了Chow检验。     

Multifactor models and their consistency with the ICAPM

Can any multifactor model be interpreted as a variant of the Intertemporal CAPM (ICAPM)? The ICAPM places restrictions on time-series and cross-sectional behavior of state variables and factors. If a state variable forecasts positive (negative) changes in investment opportunities in time-series regressions, its innovation should earn a positive (negative) risk price in the cross-sectional test of the respective multifactor model. Second, the market (covariance) price of risk must be economically plausible as an estimate of the coefficient of relative risk aversion (RRA). We apply our ICAPM criteria to eight popular multifactor models and the results show that most models do not satisfy the ICAPM restrictions. Specifically, the “hedging” risk prices have the wrong sign and the estimates of RRA are not economically plausible. Overall, the Fama and French (1993) and Carhart (1997) models perform the best in consistently meeting the ICAPM restrictions. The remaining models, which represent some of the most relevant examples presented in the empirical asset pricing literature, can still empirically explain the size, value, and momentum anomalies, but they are generally inconsistent with the ICAPM.     

Anchoring-Adjusted Capital Asset Pricing Model

What happens when the capital asset pricing model is adjusted for the anchoring and adjustment heuristic of Tversky and Kahneman [1974 Tversky, A., and D. Kahneman. “Judgment Under Uncertainty: Heuristics and Biases.” Science, 185, (1974), pp. 1124–1131.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]]? The surprising finding is that adjusting the capital asset pricing model for anchoring provides a plausible unified framework for understanding almost all of the key asset pricing anomalies. The anomalies captured in the theoretical framework include the well-known size and value effects, high alpha of low beta stocks, accruals, low volatility anomaly, momentum effect, stock splits, and reverse stock splits. The market equity premium is also larger with anchoring. This suggests that the anchoring-adjusted capital asset pricing model may provide the needed unifying structure to behavioral finance.     

A stylized model of home buyers’ and bankers’ behaviours during the 2007-2009 US subprime mortgage crisis: a predatory perspective

We examine the behaviour of market agents during the years leading to the 2008 US subprime mortgage crisis using a stylized capital asset pricing model model. In our study, an average investor eager to make money by flipping houses meets a banker who offers him subprime mortgage deals. We refer to recent research that shows the mechanics of the psychological and behavioural components of these two market agents. In particular, much in line with the famous Stanford experiment, it is assumed that investors adopt a predator or a prey position. Our analysis shows that, given a historical tendency towards financial predatory acts on the part of market agents (including buyers), government regulations should be adapted and strengthened to face this dooming reality.     

金融危机下中美保险公司Beta系数的实证研究

2007年末爆发的次贷危机对美国以及全世界的经济造成了巨大影响。作为现代金融体系重要组成部分的保险行业也受到了前所未有的冲击。以Cummins(1991)的简化保险公司模型为基础,通过对保险公司利润两大组成部分的比较,论文说明了危机如何改变保险公司的风险特征。对中美两国保险行业相关数据及Beta系数的实证研究,进一步验证了金融危机对两国保险行业的不同影响,揭示出合理的保险公司收益结构对于保险公司持续稳健经营的重要性。     

Beyond CAPM: estimating the cost of equity considering idiosyncratic risks

The present study proposes a new evaluation approach aimed at estimating the cost of equity through standardized models which consider an innovative set of firm-specific information on the main unsystematic risks which are typical of any business. Our objective is extending the Capital Asset Pricing Model (CAPM) by defining a standard formula for quantifying the premium for certain idiosyncratic risks as a function of a new set of firm-specific quantitative information. We define two econometric models, for listed and non-listed firms respectively, which consider five idiosyncratic risk factors: firm size, value factor, operating risks, financial structure and stock market price volatility. The models were tested on a sample of European non-financial companies. The empirical results show that while the CAPM systematically underestimates the cost of equity, the proposed models correctly estimate its expected value; furthermore, they show a slight improvement also in terms of estimates’ volatility. Due to their efficacy and ease of use, the proposed models represent a valid practical tool for investors, analysts and professional evaluators. This work contributes to the existing literature by proposing a typologically innovative extension of the CAPM set of explanatory variables, defining and testing new models for the estimation of the unsystematic risks’ spread of the cost of equity based on an original set of firm-specific accounting and market information.     

Currency excess returns and global downside market risk

We assess cross-sectional differences in 23 bilateral currency excess returns in an empirical model that distinguishes between US-specific and global risks, conditional on US bull (upside) or bear (downside) markets. Using the US dollar as numeraire currency, our results suggest that global downside risk is compensated in conditional and unconditional, bilateral currency excess returns. This finding is mostly driven by the emerging markets' currencies in our sample. We also find that the link between the global downside risk and risks associated with a typical carry trade strategy is much weaker for emerging markets' currencies than for developed markets' currencies.