Portfolio selection and skewness: Evidence from international stock markets

This paper finds that the returns of the world's 14 major stock markets are not normally distributed, and that the correlation matrix of these stock markets was stable during the January 1988–December 1993 time period. Polynomial goal programming, in which investor preferences for skewness can be incorporated, is utilized to determine the optimal portfolio consisting of the choices of 14 international stock indexes. The empirical findings suggest that the incorporation of skewness into an investor's portfolio decision causes a major change in the construction of the optimal portfolio. The evidence also indicate that investors trade expected return of the portfolio for skewness.     

Should there exist secondary markets for executive stock options?

This paper investigates the potential disadvantages of the secondary markets for executive stock options (ESOs). The benefits of such markets are evident, but they might also have negative effects for shareholders. Executives might, for example, use inside information to time their ESO selling. We investigate two personal motives of managers that can be assumed to affect their optimal selling decision, that is, managers' personal portfolio management issues and the use of inside information. We explore these motives by analyzing unique data from Finland, where there are secondary markets for ESOs. The results of the study support the traditional portfolio diversification hypothesis according to which managers tend to sell their ESOs when holding an ESO is equivalent to holding the underlying stock; that is, in such a case a manager's wealth is closely tied to the stock price of the firm. With respect to the use of inside information the results indicate that ESO selling activity is not related to future stock price behaviour, suggesting that managers do not use inside information to determine the selling time of their ESOs. These results imply that the existence of secondary markets for ESOs does not weaken the usefulness of ESOs as the management compensation, although the benefits of such markets are evident.     

Mean-variance optimization using forward-looking return estimates

Despite its theoretical appeal, Markowitz mean-variance portfolio optimization is plagued by practical issues. It is especially difficult to obtain reliable estimates of a stock’s expected return. Recent research has therefore focused on minimum volatility portfolio optimization, which implicitly assumes that expected returns for all assets are equal. We argue that investors are better off using the implied cost of capital based on analysts’ earnings forecasts as a forward-looking return estimate. Correcting for predictable analyst forecast errors, we demonstrate that mean-variance optimized portfolios based on these estimates outperform on both an absolute and a risk-adjusted basis the minimum volatility portfolio as well as naive benchmarks, such as the value-weighted and equally-weighted market portfolio. The results continue to hold when extending the sample to international markets, using different methods for estimating the forward-looking return, including transaction costs, and using different optimization constraints.

     

The investment value of the value premium

Value investment strategies are premised on research that value stocks outperform growth stocks. However, the research findings are dependent on the portfolio classification method that is used to sort stocks using the attributes of size and book-to-market ratios. Different stock markets contain different distributions of stocks, and in many markets, illiquidity concerns combined with a lack of investment scale, effectively create barriers to practical portfolio formations that align with the research. This study conducts a case study on one such market (Australia) and demonstrates that different methods of portfolio formation lead to different conclusions. For example, previous studies in Australia find evidence of the value premium only being present in the largest stocks, in contrast to the results from the US market. However, we find a value premium that is systematic across all size categories and generally increases inversely with size. Further, we find the well-documented size premium largely disappears once portfolios are formed that better represent feasible investment sets and once ‘penny dreadfuls’ are removed. Finally, asset pricing tests support the existence of a value premium in Australian stock returns when a more appropriate portfolio formation method is employed.     

Overreaction in the Hong Kong stock market

Overreaction reported in the equity markets of the United States, Spain, and Brazil is also observed in the Hong Kong stock market. The “loser” portfolios of the 33 stocks in the Hang Seng Index (HSI), on average, outperform the “winner” portfolios by 9.9% 1 year after the formation periods. Besides its emphasis on the importance of the Hong Kong market in international investment, this paper is unique in some special features related to the overreaction study. Hong Kong has markets for index futures and stock futures. Only three stocks are used in the portfolios. All the stocks in the HSI have large market capitalization and liquidity and can be shorted with no up-tick rule. Unlike other studies in international stock markets, the “arbitrage” portfolio of buying the loser portfolio and shorting the winner portfolio can actually be formed with minimum cost and easy execution, which makes the overreaction phenomena in this study very powerful.     

INTERNATIONAL DIVERSIFICATION OF EQUITIES AND FIXED-INCOME SECURITIES

Portfolio selection models have been applied principally to common stocks traded in the United States and in foreign stock markets. This study examines the efficient set of portfolios selected from a choice set that includes returns derived from domestic and international corporate bond and government bond indices as well as domestic and international stock indices. To assess the benefits of international multi-asset diversification, the authors examine the following issues: (1) the extent to which international and domestic fixed-income securities are included in efficient portfolios; (2) the effect on efficient set composition of using the Sharpe portfolio selection model as compared to the Markowitz portfolio selection model; (3) the sensitivity of efficient set characteristics produced from a single-index based portfolio selection model to alternative world market indices; and (4) the correspondence between expected and realized portfolio risk and return for the different portfolio selection models.     

The relationship between stock price index and exchange rate in Asian markets: A quantile regression approach

This paper uses the data of six Asian countries to estimate the relationship between stock price index and exchange rate. According to the portfolio balance effect, these two variables should be negatively related. However, since the evidence from traditional ordinary least squares estimation is not favorable, the quantile regression model is adopted to observe the various relationships between stock and foreign exchange markets. The results show an interesting pattern in the relation of these two markets in Asia, which indicates that the negative relation between stock and foreign exchange markets is more obvious when exchange rates are extremely high or low.     

Constructing inverse factor volatility portfolios: A risk-based asset allocation for factor investing

In this study, we investigate risk-based asset allocation approaches for factor investing strategies by constructing a multifactor portfolio based on the inverse weighting method. We propose the inverse factor volatility (IFV) strategy, which is the simplified variant of a factor risk parity, assuming constant factor correlation. In IFV portfolio construction, the portfolio's weights are determined by using scaled inverse factor volatility treated as a proxy for a targeted exposure in the optimization. Based on daily stock and index returns on global markets from 2002 to the end of 2017, we implemented the empirical analysis of IFV portfolios among three stock markets: Japan, Euro, and the US. The results obtained reveal that the IFV portfolios significantly outperformed market capitalization weighted portfolios by successfully acquiring factor risk premiums.     

An investigation of the stability of returns in Western European equity markets

This paper investigates the temporal stability of various dimensions of the returns of 16 European stock markets that are relevant to an analysis of international portfolio diversification. The basic data consist of daily stock market price indices for these markets. This group of indices comprehends a wide range of stock markets differentiated by size, age and technological sophistication, but in each case located in Western Europe. Two main tests were conducted: (a) ANOVA to identify inter-temporal variability and inter-market variability over 24 three-month sub-periods from January 1989 to December 1994, and (b) cluster analysis to identify groups of markets that exhibit similar behaviour patterns. The findings suggest that, while the potential gains from an internationally diversified portfolio restricted to the equities of Western European markets appear to be substantial, the lack of inter-temporal stability in the composition of the optimal portfolio from one period to another makes these gains difficult to achieve in practice.     

Volatility spillovers between oil prices and stock sector returns: Implications for portfolio management

In this article we take a recent generalized VAR-GARCH approach to examine the extent of volatility transmission between oil and stock markets in Europe and the United States at the sector-level. The empirical model is advantageous in that it typically allows simultaneous shock transmission in the conditional returns and volatilities. Insofar as volatility transmission across oil and stock sector markets is a crucial element for portfolio designs and risk management, we also analyze the optimal weights and hedge ratios for oil-stock portfolio holdings with respect to the results. Our findings point to the existence of significant volatility spillover between oil and sector stock returns. However, the spillover is usually unidirectional from oil markets to stock markets in Europe, but bidirectional in the United States. Our back-testing procedures, finally, suggest that taking the cross-market volatility spillovers estimated from the VAR-GARCH models often leads to diversification benefits and hedging effectiveness better than those of commonly used multivariate volatility models such as the CCC-GARCH of Bollerslev (1990), the diagonal BEKK-GARCH of Engle and Kroner (1995) and the DCC-GARCH of Engle (2002).     

Time and frequency dynamics of connectedness and hedging performance in global stock markets: Bitcoin versus conventional hedges

Some studies have revealed the hedging ability of Bitcoin against stock markets, but the knowledge of how it compares with other hedges is in its infancy. This paper presents the first study on time-frequency domain connectedness and hedging among five hedges (Bitcoin, crude oil, commodities, gold and the U.S. dollar (USD) index) and four stock indices (developed markets ex U.S., emerging markets ex China, U.S. and China). We find that the connectedness between hedges and stock markets varies by time across time horizons. Specifically, the connectedness between Bitcoin and stock indices is the smallest among all hedges, especially for the short horizon. Gold and USD are isolated from other markets at longer horizons. The hedging ratio, optimal portfolio weights and hedging effectiveness also vary across investment horizons. For short-term investment, gold has better hedging effectiveness, especially for emerging stock markets and the U.S. stock market. For median- and long-term investment, USD has better performance, especially for developed markets ex U.S. and emerging stock markets. Additionally, although Bitcoin has good hedging properties, it has high volatility compared with other hedging assets. In other words, if Bitcoin is included in a portfolio, investors should pay attention to its wide variation. These empirical findings highlight the important role that gold and USD play in hedging against global stock markets.     

Extreme observations and diversification in Latin American emerging equity markets

In this paper, we focus on the tails of the unconditional distribution of Latin American emerging markets stock returns. We explore their implications for portfolio diversification according to the safety first principle, first proposed by Roy [Econometrica (1952) 20, 431]. We find that the Latin American emerging markets have significantly fatter tails than industrial markets, especially, the lower tail of the distribution. We consider the implication of the safety first principle for a US investor who creates a diversified portfolio using Latin American stock markets. We find that a US investor gains by adding Latin American equity markets to her purely domestic portfolio. For different parameter specifications, we find a more realistic asset allocation than the one suggested by the literature based on the traditional mean-variance framework.     

Attention allocation and international stock return comovement: Evidence from the Bitcoin market

We employ extreme Bitcoin returns as exogenous shock events to investigate the impact of investor attention allocation on worldwide stock return comovement. We find that (1) these shock events decrease worldwide stock return comovement, (2) there is an asymmetric effect in which a crash shock event has a greater impact on return comovement than a jump shock event, and (3) the impact of these shock events on equity comovement is more pronounced in emerging markets. Our results suggest that identifying extreme Bitcoin returns will benefit portfolio construction. Our results may be of considerable interest to investors, as well as to academics interested in portfolio diversification, asset comovement, and cryptocurrencies.     

Stock market correlations during the financial crisis of 2008–2009: Evidence from 50 equity markets

Using data from 50 equity markets we examine conditional and unconditional correlations around two major banking events during the financial crisis of 2008–09. To measure the value of covariance information on the augmented DCC model used in the study, a portfolio in-sample estimation is performed. We show that by taking into account the change in the level of variance in high volatility periods, the estimates of the conditional covariance are more efficient in capturing the dynamics of the stock markets variance. Furthermore, in a two-asset allocation framework, the model consistently generates relatively low portfolio variances, implying substantial benefits in portfolio diversification.     

Dynamic correlations and hedging effectiveness between gold and stock markets: Evidence for BRICS countries

This paper examines the dynamic relationships between gold and stock markets using data for the BRICS counties. For this purpose, we estimate the Asymmetric DCC model for weekly stock and gold data. Our main objective is to examine the time-varying correlations between the two assets and to check the effectiveness of gold as a hedge for equity markets. The empirical results reveal that the dynamic conditional correlations switch between positive and negative values over the period under study. These correlations are low to negative during the major financial crises suggesting that gold can act as a safe haven against extreme market movements. We also evaluate the implications for portfolio diversification and hedging effectiveness for the gold/stock pairs. Our findings suggest that adding gold to a stock portfolio enhances its risk-adjusted return.     

Benefits of diversifying investments into emerging markets with time-varying correlations: An Australian perspective

Australian investors can reduce their overall portfolio risk by diversifying into equities from other markets. Emerging markets have attracted significant interest because of their low correlations with Australian equity market returns; however, a number of studies have indicated that correlations between equity returns are increasing over time, so using unconditional estimates of correlations in a portfolio optimization model can result in the selection of a portfolio that may not be optimal.We use an Asymmetric Dynamic Conditional Correlation GARCH model to estimate time-varying correlations and include these correlation estimates in the portfolio optimization model. The assets used for portfolio construction comprise seven emerging market indices that are available to foreign investors. This study finds that, despite increasing correlations, there are still potential benefits for Australian investors who diversify into international emerging markets.     

A Note on International Portfolio Diversification with Short Selling

In this paper, the diversification benefits of using stock index futures are examined. Empirical evidence shows that traditional diversification in international equity markets does not produce a risk adjusted performance superior to the US market. An explanation for this result is that restrictions on short selling prohibit the best allocation of resources when overseas stock markets are riskier and have worse returns. However, when such restrictions are eased for short selling in index futures markets, investors are enabled to both allocate their investments more efficiently and to construct a superior portfolio.     

On the Out-of-Sample Importance of Skewness and Asymmetric Dependence for Asset Allocation

Recent studies in the empirical finance literature have reportedevidence of two types of asymmetries in the joint distributionof stock returns. The first is skewness in the distributionof individual stock returns. The second is an asymmetry in thedependence between stocks: stock returns appear to be more highlycorrelated during market downturns than during market upturns.In this article we examine the economic and statistical significanceof these asymmetries for asset allocation decisions in an out-of-samplesetting. We consider the problem of a constant relative riskaversion (CRRA) investor allocating wealth between the risk-freeasset, a small-cap portfolio, and a large-cap portfolio. Weuse models that can capture time-varying moments up to the fourthorder, and we use copula theory to construct models of the time-varyingdependence structure that allow for different dependence duringbear markets than bull markets. The importance of these twoasymmetries for asset allocation is assessed by comparing theperformance of a portfolio based on a normal distribution modelwith a portfolio based on a more flexible distribution model.For investors with no short-sales constraints, we find thatknowledge of higher moments and asymmetric dependence leadsto gains that are economically significant and statisticallysignificant in some cases. For short sales-constrained investorsthe gains are limited.     

Illiquidity,return and risk in G7 stock markets: Interdependencies and spillovers

Trading activity in G7 stock markets reflects not only the macroeconomic and financial impact of these G7 economies in international economic growth, but also their financial interdependence. While this nexus of major stock markets has been explored in terms of volatility and return spillovers, there has been no combined analysis of return, volatility and illiquidity spillovers. We study illiquidity spillovers because they are transmissions of trading activity and, thereof, transmissions of information and market sentiment. We find that the dynamics of international stock markets are characterized by persistent illiquidity and also that illiquidity shocks are significantly correlated across markets. Furthermore, we discover Granger causal associations between risk, return and illiquidity across G7 stock market and also within each stock market. Our findings bear significance for the regulation of international financial markets and also for international portfolio diversification.     

Stock Splits and Bond Yields: Isolating the Signaling Hypothesis

One explanation offered for stock splits is that the split signals positive information by reducing the stock price range in expectation of improved future prospects. Price declines also lead to changes in stock price dynamics, but related securities are not subject to these other changes and therefore can be used to provide a separate assessment of the markets’ interpretation of the split. We examine corporate bond issues around stock splits and find a significant decline in the bond yield spread following stock splits, supporting the signaling hypothesis. We also confirm improvements in forecasted and realized earnings subsequent to stock splits.