Risk sharing and counter-cyclical variation in market correlations

I present a consumption-based dynamic asset pricing model in which international market correlations vary counter-cyclically over time. The driving force in the model is the time-varying effective risk aversion induced by external habit formation. Market returns are driven by fundamental outputs and discount rates. When risk aversion is high, the effect of discount rates on market returns rises with the market price of risk. To the extent that countries share risk, the cross-country correlation of discount rates exceeds the cross-country correlation of fundamental outputs. In bad times, market correlations rise as returns are mostly driven by discount rates. Thus, consistent with the empirical evidence, periods of high risk aversion are associated with high market correlations and high market volatility. After calibration, my model is consistent with the observed variation in market correlations, as well as other features of asset prices including the equity premium and market volatility.     

Return enhancement trading strategies for size based portfolios

Recent theoretical work suggests that definitions of market efficiency that allow for the possibility of time-varying risk-premia will generally lead to return sign predictability. Consistent with this theory, we show that a logit model based on the lagged value of the market risk premium is useful for successfully predicting the return sign for CRSP small decile portfolio returns, but not large ones. We additionally employ this model in market timing simulations of micro-cap mutual funds in which investment can actually be made. The results indicate that a market-timing strategy based on our return-sign forecasting model outperforms a buy-and-hold strategy for 13 of 14 micro-cap funds studied. On average, the buy-and-hold strategy produces an average compound return of 11.98% per annum versus an average of 16.60% for the market-timing strategy. Nevertheless, trading restrictions make the return-sign forecasting model more practical to employ by the micro-cap fund portfolio manager rather than the individual fund investor.

Optimal portfolio allocation under the probabilistic VaR constraint and incentives for financial innovation

We characterize the investor’s optimal portfolio allocation subject to a budget constraint and a probabilistic VaR constraint in complete markets environments with a finite number of states. The set of feasible portfolios might no longer be connected or convex, while the number of local optima increases exponentially with the number of states, implying computational complexity. The optimal constrained portfolio allocation may therefore not be monotonic in the state–price density. We propose a type of financial innovation, which splits states of nature, that is shown to weakly enhance welfare, restore monotonicity of the optimal portfolio allocation in the state-price density, and reduce computational complexity. We are grateful to Ken Kavajecz and seminar participants at Harvard Business School, London School of Economics, Maastrict University, ZEI Bonn, and Danske Bank Symposium on Asset allocation and Value-at-Risk: Where Theory Meets Practice for comments on an earlier version of this paper. We also benefitted from the suggestions of two anonymous referees. Our papers can be downloaded from www.RiskResearch.org.     

Is socially responsible investment useful in Mexico? A multi-factor and ex-ante review

The present paper continues the firsts reviews made to socially responsible investment in Mexico. We extended these reviews by using a non-parametric multivariate equality test, along with a multi-factor market cap model, and a Monte Carlo simulation. Our results show that the IPCS index, the IPCcomp and the IPC have a statistically equal mean-variance performance, suggesting that this sort of investment style (SRI) is a good substitute of the broad market investment style in the long term. Among the causes of this finding is the fact that the IPCS and the IPCcomp indexes have almost the same large and small cap stock concentration and the IPC index (a large-cap one) is not as diversified and mean-variance efficient as the former.     

The demand for eurozone stocks and bonds in a time-varying asset allocation framework

This paper analyzes the short and long-run demand for traditional financial asset classes in eleven founding eurozone members. Our sample period starts from the introduction of euro till 2017. We calculate the welfare losses stemming from ignoring the demand for domestic and eurozone equities and bonds, for various levels of risk aversion. Our results show that the bonds of eurozone countries are, in general, desirable for short-run only. However, in Ireland, Portugal and Spain the bonds are desirable for both short-run and long-run investment horizons. Stocks exhibit both short-run and long-run desirability for all countries except Greece. The Greek stocks are desirable for short- run only.     

Leveraging a call-put ratio as a trading signal

We examine whether a put-call ratio, derived from a unique set of market data, can be used to predict directional moves in asset prices during various market conditions between March 2005 and December 2012. Our findings show: (1) specific market participant's options trading volume is a predecessor to asset price movements, and (2) portfolios based on the put-call ratio adjusted for four factors Carhart model and transaction costs exhibit abnormal excess returns.     

Flexible distribution functions,higher-order preferences and optimal portfolio allocation

In this paper we show that flexible probability distribution functions, in addition to being able to capture stylized facts of financial returns, can be used to identify pure higher-order effects of investors' optimizing behavior. We employ the five-parameter weighted generalized beta of the second kind distribution—and other density functions nested within it—to determine the conditions under which risk averse, prudent and temperate agents are diversifiers in the standard portfolio choice theory. Within this framework, we illustrate through comparative statics the economic significance of higher-order moments in return distributions.     

The role of transaction costs and risk aversion when selecting between one and two regimes for portfolio models

Estimation of the inputs is the main problem when applying portfolio analysis, and Markov regime-switching models have been shown to improve these estimates. We investigate whether the use of two-regime models remains superior across a range of values of risk aversion and transaction costs, in the presence of skewness and kurtosis and no short sales. Our results for US data suggest that, due to differences in their risk preferences and transactions costs, most retail investors may prefer to use one-regime models, while investment banks may prefer to use two-regime models.     

风险投资、行业经验与创业企业专利组合策略研究

长期以来,对于风险投资能否促进以及如何促进创业企业创新能力在学术界和实践界存在广泛争议,揭示风险投资对创业企业专利组合策略的影响是解决这一问题的关键,但相关研究比较薄弱。以2009-2014年中小板和创业板上市创业企业为样本,利用倾向得分匹配法（PSM）建立实验组和对照组,采用发明专利技术范围和专利重点衡量专利组合策略,实证检验风险投资对创业企业专利组合策略的影响,并进一步检验风险投资是否通过行业经验发挥作用。结果表明,风险投资能拓宽创业企业的专利技术范围,帮助创业企业形成专利重点,风险投资行业经验是影响创业企业专利技术范围的重要因素,但其并未对专利重点发挥作用。研究结论对优化我国创业企业专利战略具有重要实践意义。     

政府干预的新度量——基于最终控制人投资组合的视角

在度量政府干预时,已有文献往往将企业视为一个整体,通过比较政府干预指标的横截面差异来确定企业受政府干预的强弱。然而,在中国的制度背景下,最终控制人(例如:地方政府)往往控制着多家企业。此时,将同一最终控制人控制的企业视为一个投资组合,通过比较企业在投资组合中的差异来度量政府干预,应该更为恰当。基于这一思路,我们以最终控制人到公司的控制权与公司规模为权重指标,构建了公司在其最终控制人投资组合中的重要性指数,并将其作为政府干预的衡量指标。以地方国有上市公司为样本,实证结果显示:当公司在其最终控制人的投资组合中越重要时,公司的政策性负担(税收负担与超额雇员)越沉重、过度投资越严重、从而市场价值越低。此外,这类公司也越多的获得了政府补助。我们还发现,本文构建的政府干预指标相比同类指标有更好的解释力。这些结果印证了本文所构建政府干预指标的合理性。