Correlation and spillover effects between the US and international banking sectors: New evidence and implications for risk management

This paper quantitatively examines return transmission and volatility spillovers between banking sector stocks in the US and eight other countries by applying our newly extended VAR-DCC-MEGARCH-M model with asymmetric spillovers and Student-t or skew-t errors. Our investigations clarify almost unidirectional stock return transmission from the US banking sector to all other eight international banking sectors. In addition, we also uncover bidirectional volatility spillovers between the US and other eight international banking sector stocks, which are all tied to the leverage effect. Moreover, using the dynamic conditional variances and covariances from our extended model, we derive the time-varying optimal hedge ratios and optimal portfolio weights. These analyses reveal that, except for such extraordinary periods as during financial crises, we can hedge the US banking sector stocks with other international banking sector stocks, and that well-balanced portfolios of the US and other banking sector stocks are optimal. Furthermore, additional analysis using gold, silver, and platinum futures reveals that we can hedge international banking sector stocks with precious metal futures highly effectively, and that well-balanced portfolios of banking stocks and precious metals are optimal. Based on the results from our analyses, this paper derives many significant interpretations and implications for financial and systemic risk management.     

Predictability and diversification benefits of investing in commodity and currency futures

We re-examine diversification benefits of investing in commodities and currencies by considering a risk-averse investor with mean-variance preferences who exploits the possibility of predictable time variation in asset return means, variances, and covariances. We implement unconditional and conditional efficient portfolio strategies designed to exploit this predictability, together with more traditional and/or ad hoc ones yet hitherto relatively unexplored in this context (including the equally weighted, fixed weight, volatility timing, and reward-to-risk timing strategies). We find that, for all portfolio strategies, commodities and currencies do not improve the investment opportunity set of the investor with an existing portfolio of stocks, bonds and T-bills, and an investment horizon of one month. Our findings, which reverse the conclusions of previous studies that focus on static portfolio strategies, are robust across several performance metrics.     

Realized (co)variances of eurozone sovereign yields during the crisis: The impact of news and the Securities Markets Programme

We use realized variances and covariances based on intraday data to measure the dependence structure of eurozone sovereign yields. Our analysis focuses on the impact of news, obtained from the Eurointelligence newsflash, on the dependence structure. More news tends to raise the volatility of yields of financially-distressed countries and to decrease the covariance of distressed countries’ yields with German bond yields, suggesting a potential flight-to-quality effect. Common news about the euro crisis and news about specific countries tend to raise the covariance of yields between distressed countries, indicating potential crisis spill-over effects. However, we do not detect spillover effects from news about third countries to the covariance between other country pairs. Bond purchases by the ECB under its Securities Markets Programme (SMP) mitigate the negative crisis spillovers among the distressed countries and reduce the potential flight-to-quality from the distressed countries to Germany.     

Foreign exchange market return spillovers and connectedness among African countries

This paper examines the foreign exchange return shock spillovers and network connectedness among African countries during crisis periods using (Diebold & Yilmaz, 2012; 2014; 2016) which is based on generalized VAR and network theory between June 2004 and June 2021. Overall, the study found a low system-wide spillover connectedness among African foreign exchange markets. However, the total systemic spillover index increased during the eurozone sovereign debt crisis followed by global financial crisis, indicating evidence of contagion effects. This offers good diversification opportunities in the African currency market during crisis periods. The study also found no significant evidence of spillover effects among African currencies. Nonetheless, the network connectedness analysis found a positive significant pairwise return spillovers from the South African rand, Moroccan dirham and the CFA francs to Botswana pula, and from Moroccan dirham to CFA francs and South African rand. Furthermore, the study found South African rand, Moroccan dirham and CFA francs as the most significant net-transmitter of return shocks to other currencies whiles the Kenyan shilling and Botswana pula are the net-receivers of return shocks from other currencies. These results have implications for African central banks interventions in stabilizing their exchange rates to facilitate intra and inter-African trade and for international portfolio investors in managing their foreign exchange risk exposures.     

Does economic policy uncertainty drive the dynamic spillover among traditional currencies and cryptocurrencies? The role of the COVID-19 pandemic

The paper examines the dynamic spillover among traditional currencies and cryptocurrencies before and during the COVID-19 pandemic and investigates whether economic policy uncertainty (EPU) impacts this spillover. Based on the TVP-VAR approach, we find evidence of spillover effects among currencies, which increased widely during the pandemic. In addition, results suggest that almost all cryptocurrencies remain as “safe-haven” tools against market uncertainty during the COVID-19 period. Moreover, comparative analysis shows that the total connectedness for cryptocurrencies is lower than for traditional currencies during the crisis. Further analysis using quantile regression suggests that EPU exerts an impact on the total and the net spillovers with different degrees across currencies and this impact is affected by the health crisis. Our findings have important policy implications for policymakers, investors, and international traders.     

Assessing the extreme risk spillovers of international commodities on maritime markets: A GARCH-Copula-CoVaR approach

Maritime market relies on demand of international commodity trade from producers to consumers. Focusing on measuring the inherent correlation, this paper employs a GARCH-Copula-CoVaR approach to address the debate on the extreme risk spillovers from commodity market to maritime market. Our results provide new evidence regarding risk transmission from oil and ex-energy sector to the maritime markets, as well as the interactions between different sub-sectors of maritime market. It is also found that commodity markets exert different spillover effects on global and Chinese domestic maritime markets. In additional, the risk spillovers in oil-freight index pairs after global financial crisis is different from the before. Results enrich the knowledge of risk spillovers between commodity and maritime market, which help stakeholders improve portfolio optimization.     

Hedging inflation risk in a developing economy: The case of Brazil

Inflation shocks are one of the pitfalls of developing economies and are usually difficult to hedge. This paper examines the optimal strategic asset allocation for a Brazilian investor seeking to hedge inflation risk at different horizons, ranging from one to 30 years. Using a vector-autoregressive specification to model inter-temporal dependency across variables, we measure the inflation hedging properties of domestic and foreign investments and carry out a portfolio optimisation. Our results show that foreign currencies complement traditional assets very efficiently when hedging a portfolio against inflation: around 70% of the portfolio should be dedicated to domestic assets (equities, inflation-linked (IL) bonds and nominal bonds), whereas 30% should be invested in foreign currencies, especially the US dollar and the euro.     

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).     

Investigating tail-risk dependence in the cryptocurrency markets: A LASSO quantile regression approach

We construct the complete network of tail risk spillovers among major cryptocurrencies using the Least Absolute Shrinkage and Selection Operator (LASSO) quantile regression. We capture important features of the network, including major risk-driving and major risk-receiving currencies, and the evolution of the tail dependence among the currencies over time. Importantly, we reveal a striking finding that the right tail dependence among the cryptocurrencies is significantly stronger than the left tail counterpart. This unique characteristic may have contributed to the rise in popularity of cryptocurrencies over the last few years. Our portfolio analysis reveals that diversification in cryptocurrency investment can be accomplished simply by employing the naïve equal-weighted scheme even when transaction costs are taken into account.     

Conditional covariances and direct central bank interventions in the foreign exchange markets

In this paper, we investigate the effects of central bank interventions (CBIs) on the ex post correlation and covariance of exchange rates. Using a multivariate GARCH model with time-varying conditional covariances, we estimate the effects of CBIs on both the variances and covariance between the yen and the deutsche mark (the Euro) in terms of the US dollar. Our results suggest that coordinated CBIs not only tend to increase the volatility of exchange rates but also explain a significant amount of the covariance between the major currencies. We show that this result can be useful for short-run currency portfolio management.     

International portfolio selection with exchange rate risk: A behavioural portfolio theory perspective

This paper analyzes international portfolio selection with exchange rate risk based on behavioural portfolio theory (BPT). We characterize the conditions under which the BPT problem with a single foreign market has an optimal solution, and show that the optimal portfolio contains the traditional mean–variance efficient portfolio without consideration of exchange rate risk, and an uncorrelated component constructed to hedge against exchange rate risk. We illustrate that the optimal portfolio must be mean–variance efficient with exchange rate risk, while the same is not true from the perspective of local investors unless certain conditions are satisfied. We further establish that international portfolio selection in the BPT with multiple foreign markets consists of two sequential decisions. Investors first select the optimal BPT portfolio in each market, overlooking covariances among markets, and then allocate funds across markets according to a specific rule to achieve mean–variance efficiency or to minimize the loss in efficiency.     

Cross‐market spillovers with ‘volatility surprise’

This article adopts the asymmetric DCC with one exogenous variable (ADCCX) model developed by Vargas (2008), by updating the concept of ‘volatility surprise’ to capture cross-market relationships. Current methods for measuring spillovers do not focus on volatility interactions, and neglect cross-effects between the conditional variances. This paper aims to fill this gap. The dataset includes four aggregate indices representing equities, bonds, foreign exchange rates and commodities from 1983 to 2013. The results provide strong evidence of spillover effects coming from the ‘volatility surprise’ component across markets. Against the background of the recent financial crisis, the aim is to contribute to the literature on the interdependencies of financial markets, both in conditional means and (co)variances. In addition, asset management implications are derived.     

SYMMETRIC VERSUS ASYMMETRIC CONDITIONAL COVARIANCE FORECASTS: DOES IT PAY TO SWITCH?

Volatilities and correlations for equity markets rise more after negative returns shocks than after positive shocks. Allowing for these asymmetries in covariance forecasts decreases mean‐variance portfolio risk and improves investor welfare. We compute optimal weights for international equity portfolios using predictions from asymmetric covariance forecasting models and a spectrum of expected returns. Investors who are moderately risk averse, have longer rebalancing horizons, and hold U.S. equities benefit most and may be willing to pay around 100 basis points annually to switch from symmetric to asymmetric forecasts. Accounting for asymmetry in both variances and correlations significantly lowers realized portfolio risk.     

Time-Varying Spillover and the Portfolio Diversification Implications of Clean Energy Equity with Commodities and Financial Assets

This article examines the time-varying spillover and its implications on hedging and portfolio diversification for clean energy equities (WilderHill New Energy Global Innovation Index (NEX)) with technology stocks (PSE), four energy sub-indices of Standard & Poor Goldman Sachs Commodity Index (S&P-GSCI) viz., Crude oil, Brent crude oil, Gasoline and Heating oil and three major global equities indices represented by the USA, Europe, World, Dow-Jones Islamic Market Index (DJIMI) along with USD-Euro exchange rate. We find that in a mixed portfolio set-up, the inclusion of NEX in energy portfolio provides better diversification and risk reduction benefits for hedgers and portfolio managers.     

外汇风险传染网络测度与影响机制分析--基于静态和动态的双重视角

国际争端频发及不确定性风险增加的外部环境,叠加经济下行压力增大的内部环境,致使汇率波动变得更加敏感,外汇风险传染危害性提升。基于1999-2018年全球50种主要货币,本文引入复杂网络模型以及静态与动态两类相关系数算法,分析了汇率网络的总体关联性及各货币风险吸收效应和外溢效应。同时,本文采用混合效应面板回归研究了资本账户开放、汇率制度改革等政策因素的作用,在此基础上,分析了外汇风险传染的影响机制。研究发现,考察期内,各货币波动溢出比收益率溢出更平稳,收益率溢出关系稳定性相对较弱、变动幅度更大,这与金融危机和欧债危机爆发有关。全球主要货币总体关联性具有明显的时变特征和区制特征,且波动溢出与收益率溢出存在区制同步性。资本账户开放和汇率制度是外汇风险传染的重要影响因素,汇率市场化改革有助于缓释外汇风险传染,而资本账户开放将扩大外汇风险传染效应。     

Downside and upside risk spillovers between exchange rates and stock prices

We examined downside and upside risk spillovers from exchange rates to stock prices and vice versa for a set of emerging economies. We characterized the dependence structure between currency and stock returns using copulas and computed downside and upside value-at-risk and conditional value-at-risk. We documented a positive relationship between stock prices and currency values in emerging economies with respect to the US dollar and the euro, with downside and upside spillover risk effects transmitted both ways. Finally, we also documented asymmetries in upside and downside risk spillovers and asymmetric differences in the size of risk spillovers when the domestic currency values against the US dollar and the euro. Our results, consistent with flight-to-quality phenomena, have implications for downside and upside risk management of international investor portfolios in emerging markets.     

Factor investing and currency portfolio management

Currency-specific pricing factors are pervasive in international asset pricing. However, portfolio and risk management based on forex factors, instead of individual currencies, are rarely discussed. This paper tries to fill this gap by modelling dynamic correlations and non-normality among forex factors. By considering the four most popular forex factors: the dollar risk factor, the carry trade factor, the currency momentum factor, and the currency value factor, we find that a dynamic conditional correlation copula (DCC-copula) model with skewed-t kernel fits the joint distribution well. We show that, for risk-averse investors who focus on factor investing or employ the forex factors to resize the specific risk exposure, ignoring the tail dependence structure of forex factors brings significant costs.     

The extreme risk connectedness of the new financial system: European evidence

The paper empirically analyses the tail risk connectedness between FinTech and the banking sector in the European context over 2015–2022. For this purpose, we use the Tail-Event driven NETworks (TENET) risk model, i.e., we can capture the behaviour of extreme (negative and positive) risk spillover within the financial system. The results highlight how most tail risk spillovers are from banks to FinTech firms. Also, the findings suggest that the spillovers of cross-sector tail risk are more significant in downside (bearish) risk conditions than in upside (bullish) one. We find evidence of an asymmetric effect of extreme risk spillover to the real economy. Finally, we evaluate the monetary policy’s impact on extreme risk. Our findings highlight the importance of closer monitoring risk spillover between FinTech institutions and the European banking system to maintain financial stability.     

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.     

Impacts of COVID-19 outbreak,macroeconomic and financial stress factors on price spillovers among green bond

We examine the impacts of the COVID-19 pandemic and global risk factors on the upside and downside price spillovers of MSCI global, building, financial, industrial, and utility green bonds (GBs). Using copulas, CoVaR, and quantile regression approaches, we show symmetric tail dependence between MSCI global GB and both building and utility GBs. Moreover, the upper tail dependence between MSCI global GB and financial GB intensified during COVID-19. We find asymmetric risk spillovers from MSCI global GB to the remaining GBs. Finally, the COVID-19 spread, the Citi macro risk index, and the financial condition index contribute positively to the quantiles' risk spillovers. The spillover index method shows significant dynamic volatility spillovers from global GB to GB sectors that intensify during the pandemic outbreak, except for financial GB. The causality-in-mean and in-variance from COVID-19, Citi macro risk index, and US financial condition index to the downside and upside spillover effects are sensitive to quantiles