Portfolio choice with high frequency data: CRRA preferences and the liquidity effect

This paper suggests a new approach for portfolio choice. In this framework, the investor, with CRRA preferences, has two objectives: the maximization of the expected utility and the minimization of the portfolio expected illiquidity. The CRRA utility is measured using the portfolio realized volatility, realized skewness and realized kurtosis, while the portfolio illiquidity is measured using the well-known Amihud illiquidity ratio. Therefore, the investor is able to make her choices directly in the expected utility/liquidity (EU/L) bi-dimensional space. We conduct an empirical analysis in a set of fourteen stocks of the CAC 40 stock market index, using high frequency data for the time span from January 1999 to December 2005 (seven years). The robustness of the proposed model is checked according to the out-of-sample performance of different EU/L portfolios relative to the minimum variance and equally weighted portfolios. For different risk aversion levels, the EU/L portfolios are quite competitive and in several cases consistently outperform those benchmarks, in terms of utility, liquidity and certainty equivalent.     

Asymmetric Conditional Volatility and Firm Size: Evidence from Australian Equity Portfolios

This paper examines the relationship between firm size and equity volatility for two portfolios of Australian equities. Univariate and Multivariate GARCH models are used to demonstrate that conditional variance is related to firm size. There is strong evidence to suggest that the variance-covariance matrix of returns is time varying and asymmetric. A negative innovation to the return of the large firm portfolio results in higher levels of conditional volatility in the small firm portfolio than would be the case for a positive innovation of equal magnitude. News about own returns appears to determine the conditional variance of the portfolio of large firms. The conditional covariance between the two portfolios also displays evidence of asymmetry.     

Forecast of realized covariance matrix based on asymptotic distribution of the LU decomposition with an application for balancing minimum variance portfolio

We derive the asymptotic distribution for the LU decomposition, that is, the Cholesky decomposition, of realized covariance matrix. Distributional properties are combined with an existing generalized heterogeneous autoregressive (GHAR) method for forecasting realized covariance matrix, which will be referred to as a generalized HARQ (GHARQ) method. An out-of-sample forecast comparison of a real data set shows that the proposed GHARQ method outperforms other existing methods in terms of optimizing the variances of portfolios.     

On the Fisher information matrix of a vector ARMA process

We derive a neat and compact representation of the asymptotic Fisher information matrix of a vector ARMA process. Its inverse can be used immediately as the asymptotic covariance matrix of the Gaussian maximum likelihood estimator. We also provide the robust sandwich covariance estimator when the process is non-Gaussian.     

Panel data analysis of multi-factor capital asset pricing models

In this article, we propose MFCAPM panel models with fixed effects and test theories associated with risk exposures and anomalies postulated by Fama and French, and we assess their out-of-sample predictive performances. Based on the portfolios formed by French, we construct 10 panel models, each consisting of 10 portfolios grouped by size deciles, and another 10 panels by value deciles. In the presence of cross-section dependence, the MFCAPM panel model is estimated by the feasible generalized least squares (FGLS) method for the sample period 1963(1)-2018(9). The results show that the market, firm-size and value risk exposures are significant and robust across three-, five- and six-factor panel models. Significant time-fixed effects indicate that there are several portfolios resilient to dot.com bubble peak in 2000, while some others resilient to GFC in 2007. We estimate the models for the in-sample period 1963(1)–1999(12) and generate the out-of-sample portfolio returns for the period 2000(1)–2018(9). We find that portfolio returns forecasts generated by the six-factor panel model are superior to other MFCAPM panel models, mostly due to the momentum factor (investor behaviour) explaining large return variations and volatility exposures. The findings have implications for investors, security traders and portfolio risk managers.     

Regional and copula estimation effects on EU and US energy equity portfolios

ABSTRACT

The aim of this paper is to investigate the regional interdependence structure of energy equities in the US and in the EU. Based on weekly stock prices of 28 big energy firms in the two regions from 2008 to 2019, we compare the efficiency of using bivariate or multivariate copulas to describe the dependence structure of energy equities. Furthermore, we investigate the impact of the choice between these two methods on the performance of energy equity portfolios. Our empirical results show that multivariate copulas, such as C-Vine, allow to better describe the dependence structure of energy equities. We also find that there is a stronger and more complex dependence structure among EU energy equities than among US energy equities. Our scenario analysis also shows that the dependence structure is stronger during the GFC while being weaker during the ESDC. More importantly, the correlation matrix obtained from the multivariate copula method allows to obtain optimal mean-CVaR portfolios with a higher performance than that from the bivariate copula method. More importantly, optimal portfolios constituted with multivariate copulas allow to reduce the portfolio’s sensitivity to oil prices.     

An alternative approach for portfolio performance evaluation: enabling fund evaluation relative to peer group via Malkiel’s monkey

We propose an implementable portfolio performance evaluation procedure that compares a portfolio with respect to the portfolios constructed by an infinite number of Malkiel’s blindfolded monkeys, or equivalently the whole enumeration of all possible portfolios. We argue that this approach exhibits two main advantages. First, it does not require any benchmark portfolios because a portfolio is being compared to an infinite number of portfolios. Second, it is market condition invariant. Since the market conditions are already reflected in the portfolio performances of an infinite blindfolded monkeys, our measure of portfolio performances is invariant to volatile market conditions.     

Dynamic causality between the U.S. stock market,the Chinese stock market and the global gold market: implications for individual investors’ diversification strategies

This paper proposes a generalization of the prior VAR and EGARCH model to explore the linkage between returns and volatility transmissions in the U.S. stock market, the Chinese stock market, and the global gold market from 10 July 1996 to 20 July 2018. We found that past returns of the U.S. stock market can predict the current returns of the other two markets, and that significant reciprocal volatility transmission existed within and across all three markets. We further implemented average out-of-sample (OOS) forecasting to show that a risk-adjusted portfolio, such as mean-variance with sample estimator, does not outperform an equal-weighted portfolio. This provides insights for individual investors and helps to explain the ongoing disagreement in the portfolio literature concerning the effectiveness of risk-adjusted portfolios and equal-weighted portfolios when the number of assets is small.     

New evidence on taxes and portfolio choice

Identifying the effect of differential taxation on portfolio allocation requires exogenous variation in marginal tax rates. Marginal tax rates vary with income, but income surely affects portfolio choice directly. In systems of individual taxation – like Canada's – couples with the same household income can face different effective tax rates on capital income when labor income is distributed differently within households. Using this source of variation we find portfolio responses to taxation among more affluent households. The estimated effects are statistically significant but economically modest. In a “placebo” test, using data from the U.S. (which has joint taxation), we find no effect of the intra-household distribution of labor income on portfolios.     

Controlling portfolio skewness and kurtosis without directly optimizing third and fourth moments

In spite of their importance, third or higher moments of portfolio returns are often neglected in portfolio construction problems due to the computational difficulties associated with them. In this paper, we propose a new robust mean–variance approach that can control portfolio skewness and kurtosis without imposing higher moment terms. The key idea is that, if the uncertainty sets are properly constructed, robust portfolios based on the worst-case approach within the mean–variance setting favor skewness and penalize kurtosis.     

The risk-return relations: evidence from the Korean and Taiwan stock markets

This article examines the risk-return relations conditional on up and down market periods in the Korean and Taiwan stock markets. Based on statistical tests adjusted for the effects of heteroskedasticity and autocorrelation of the residuals, beta is found positively (negatively) related to realized returns in up (down) markets. However, the results are sensitive to portfolio aggregation methods. Its role as a risk measure vanishes in down markets for the two-way (beta-size and size-beta) sorted portfolios. Unsystematic risk is significantly and positively priced only in up markets and mainly for beta-sorted portfolios while total risk is correctly priced except in Taiwan during down markets. Moreover, the impact of skewness and kurtosis on realized returns is not only sensitive to portfolio aggregation methods but also different across stock markets. They are found to be more relevant risk characteristics in the Korean than in the Taiwan stock market.     

Predicting stock realized variance based on an asymmetric robust regression approach

This paper introduces an asymmetric robust weighted least squares (ARLS) approach to improve the forecasting performance of the heterogeneous autoregressive model for realized volatility. The ARLS approach down-weights extreme observations to limit the bad influence of outliers on the estimated parameters. Compared with existing robust regression methods, our model further takes into account the asymmetry of outliers using a class of kernel functions. Out-of-sample results show the ARLS approach can generate more accurate forecasts of the S&P 500 index realized volatility in the statistical and economic senses. The model that considers the asymmetry of outliers gains superior performance among various robust regression competitors. The forecasting improvements also hold in other international stock markets. More importantly, the source of the predictive ability of the ARLS model comes from the less biased and more efficient parameter estimation.     

Optimal and investable portfolios: An empirical analysis with scenario optimization algorithms under crisis market prospects

This paper develops scenario optimization algorithms for the assessment of investable financial portfolios under crisis market outlooks. To this end, this research study examines from portfolio managers' standpoint the performance of optimum and investable portfolios subject to applying meaningful financial and operational constraints as a result of a financial turmoil. Specifically, the paper tests a number of alternative scenarios considering both long-only and long and short-sales positions subject to minimizing the Liquidity-Adjusted Value-at-Risk (LVaR) and various financial and operational constraints such as target expected return, portfolio trading volume, close-out periods and portfolio weights. Robust optimization algorithms to set coherent asset allocations for investment management industries in emerging markets and particularly in Gulf Cooperation Council (GCC) financial markets are developed. The results show that the obtained investable portfolios lie off the efficient frontier, but that long-only portfolios appear to lie much closer to the frontier than portfolios including both long and short-sales positions. The proposed optimization algorithms can be useful in developing enterprise-wide portfolio management models in light of the aftermaths of the most-recent financial crisis. The developed methodology and risk optimization algorithms can aid in advancing portfolio management practices in emerging markets and predominantly in the wake of the latest credit crunch.     

Self‐Directed Pensions: Gender,Risk, and Portfolio Choices*

In this paper, I investigate gender differences in financial risk‐taking from a new perspective, and I show that gender plays a different role across the risk distribution. To evaluate risk‐taking, I exploit portfolio choices following a reform that entitles almost the entire Swedish workforce to choose a risk profile for a part of their public‐pension contributions. The novel finding is that portfolio risk does not differ much between the men and women who choose less risky portfolios, while the men who choose risky portfolios take on significantly more risk than do the women who choose risky portfolios. The findings are robust to investors choosing the default alternative, chasing past returns, rebalancing, and different measures of risk‐taking.     

Optimizing tracking error-constrained portfolios

Active portfolios subject to tracking error (TE) constraints are the typical setup for active managers tasked with outperforming a benchmark. The risk and return relationship of such constrained portfolios is described by an ellipse in traditional mean-variance space and the ellipse’s flat shape suggests an additional constraint which improves the performance of the active portfolio. Although subsequent work isolated and explored different portfolios subject to these constraints, absolute portfolio risk has been consistently ignored. A different restriction – maximization of the traditional Sharpe ratio on the constant TE frontier in absolute risk/return space – is added here to the existing constraint set, and a method to generate this portfolio is explained. The resultant portfolio has a lower volatility and higher return than the benchmark, it satisfies the TE constraint and the ratio of excess absolute return to risk is maximized (i.e. maximum Sharpe ratio in absolute space).     

Further evidence on international Islamic and conventional portfolios diversification under regime switching

This article investigates the comparative performance of International Islamic and conventional portfolio diversification across different financial market regimes and provides an optimal choice from an American investor’s viewpoint during the period 2002–2014. Using a bootstrap-based stochastic dominance (SD) test and monthly MSCI prices of Islamic stock market indices and their conventional counterparts in 38 countries from North and Latin America, Europe and Asia-Pacific regions, we find that SD relationships between Islamic and conventional optimal-diversified portfolios change systematically according to investment region and market regime. Essentially, for all regimes, US investors are indifferent between Islamic diversification and its conventional counterpart, which implies that arbitrage diversification opportunities are rare and short lived in all regions. However, across all regions, especially in a crisis regime, Islamic portfolio diversification can be a good substitute for conventional diversification. Islamic portfolio diversification in North and Latin America, Europe and Global regions is an optimal choice for the risk-averse American investors. Finally, results imply that portfolio diversification among Islamic market indices can be a good hedge, offering investors superior investment alternatives during any financial meltdown or economic slowdown due to the conservative nature of Sharia-compliant investments.     

The Effect of Ex Ante Price on Momentum Profits

We find a strong effect of component stock prices (as of one year before the returns-ranking period) on the magnitude and duration of momentum. Relative strength portfolios formed of high-priced stocks earn statistically significant momentum profits for any holding period in the first three to four years. The effective annual return of the high-priced momentum portfolio for the first year is economically significant at 18.4%, after controlling for the capitalization, trading volume, and unconditional mean effects. This return is considerably higher than the 11.3% earned by low-priced momentum portfolios. Although the price level is correlated with capitalization and trading volume, the price effect is not a mere manifestation of the capitalization and volume effects, as it endures even when the other factors are controlled for. We discuss several implications of our results for the existing behavioral and risk-based explanations of momentum, as none of these models have an explicit role for the price effect.     

Vertical alliance portfolios and the business performance of small technology-based firms

This paper discusses how small technology-based firms (STBFs) effectively manage vertical alliances by choosing proper alliance structures to both manage challenges and pursue higher performance. We consider the main challenges of STBFs’ vertical alliances as opportunistic risk and coordination concern between partners, and derive four types of vertical alliance portfolios with different extents of risk and return based on the relational perspective. We then examine the impact of each portfolio on performance and the moderating effect of STBFs’ age and technological capability. The results show the portfolio focusing on bilateral alliances is not helpful for STBFs, while the others are useful. The portfolio focusing on unilateral alliances promises young firms better performance, while hybrid portfolios of unilateral and bilateral alliances are more helpful for older STBFs. In hybrid portfolios, bilateral alliance in the upstream is beneficial to specific technology-focused firms, while bilateral alliance in the downstream is recommended to STBFs whose technology covers a wider range.     

创业企业联盟组合规模与绩效关系实证研究——资源冗余的调节作用

面对激烈的竞争,企业希望通过构建联盟、形成联盟组合的方式应对竞争。不过,联盟组合规模对于焦点企业绩效的影响尚未得到一致结论。本文基于交易成本理论和资源基础理论,采用中国深圳创业板上市公司数据,探讨创业企业存在资源冗余的情况下,联盟组合规模与企业绩效之间的关系。采用多元层次回归的方法,对336个企业的1455条“企业-年度”的联盟组合规模相关数据分析后发现,创业企业联盟组合规模的增加对焦点企业绩效有显著的负向影响,已吸收资源冗余和未吸收资源冗余在联盟组合规模与焦点企业绩效之间起正向的调节作用,强化了联盟组合规模对焦点企业绩效的负向影响。     

Causal ordering and inference on acyclic networks

This paper develops a new identification result for the causal ordering of observation units in a recursive network or directed acyclic graph. Inferences are developed for an unknown spatial weights matrix in a spatial lag model under the assumption of recursive ordering. The performance of the methods in finite sample settings is very good. Application to data on portfolio returns produces interesting new evidences on the contemporaneous lead–lag relationships between the portfolios and generates superior predictions.