Risk transmission between Islamic and conventional stock markets: A return and volatility spillover analysis

This paper contributes to the current debate on the empirical validity of the decoupling hypothesis of the Islamic stock market from its mainstream counterparts by examining return and volatility spillovers across the global Islamic stock market, three main conventional national stock markets (the US, the UK and Japan) and a number of influential macroeconomic and financial variables over the period from July 1996 to June 2016. To that end, the VAR-based spillover index approach based on the generalized VAR framework developed by Diebold and Yilmaz (2012) is applied. The empirical analysis shows strong interactions in return and volatility among the global Islamic stock market, the conventional stock markets and the set of major risk factors considered. This finding means that the Islamic equity universe does not constitute a viable alternative for investors who wish to hedge their investments against the vagaries of stock markets, but it is exposed to the same global factors and risks hitting the conventional financial system. Therefore, this evidence leads to the rejection of the decoupling hypothesis of the Islamic stock market from conventional stock markets, which has significant implications for faith-based investors and policy makers in terms of portfolio diversification, hedging strategies and contagion risk.     

Time-varying evidence of efficiency,decoupling, and diversification of conventional and Islamic stocks

This study investigates the efficiency of conventional and Islamic stock markets and their diversification potential by using multifractal de-trended fluctuation analysis (MF-DFA), wavelet squared coherence (WTC) and wavelet Value-at-Risk (VaR). Evidence from regional and country-level markets indicates Islamic stocks are less efficient than conventional ones in the short term, however more efficient in the medium term. Conventional stocks in the UK, Japan, and emerging markets are more efficient than the Islamic ones in the long term, whereas those from the US and Europe are less efficient. The wavelet VaR shows that conventional stock markets are at least as risky as the Islamic ones.     

Do Islamic stock indices perform better than conventional counterparts? An empirical investigation of sectoral efficiency

Literature is rife with studies on efficiency of stock markets and financial performance aspects. One such aspect is the measurement of sectoral efficiency amongst stock markets. While there are several studies analysing sectorial efficiency, there is no study on the efficiency of Islamic sector indexes. The rise of Islamic indices has raised the question and multiple studies have been undertaken in exploring and validating the better performance from a risk return framework for the Islamic indices. This study attempts to pioneer in this niche area by conducting a comparative analysis of 10 sectoral global indices for both conventional and Islamic counterpart spanning over 18 years. The sample time period runs from 1 January 1996 until 31 December 2014. To further validate our study, we have divided our data into four major time periods, to factor in different phases the world markets have gone through in the sample period, i.e. 1996–2000; 2001–2002; 2003–2006 and 2006 to 2014. The methodology selected in understanding the efficiency of these sectoral stock indices is the multifractal de-trended fluctuation analysis (MFDFA). Our analysis reveals that in the shorter horizon, efficiency tends to follow a similar pattern amongst the conventional and Islamic counterpart. Furthermore, Islamic sectoral indices generally tend to exhibit a higher efficiency regime across the last decade. Overall, Islamic index seems to have stayed attractive and resilient, allowing conformity with the weak form efficient market hypothesis.     

On the volatility spillover between lslamic and conventional stock markets: A quantile regression analysis

This paper aims at analyzing the degree and structure of interdependencies in terms of volatility (transmission, contagion) between Islamic and conventional stock markets on calm periods and at times of financial fragility and crisis. We focused on the recent financial instability periods and used the Quantile Regression-based GARCH model. Main results lead to very interesting conclusions. First, it has been found that Islamic stock markets are not totally immune to the global financial crisis. Second, a very strong interdependence is sensed from the conventional to the Islamic stock markets, especially, from the conventional developed markets to the Islamic Emerging and Arab markets and to the Islamic developed markets. Finally, it has been proved that the interdependencies from conventional to Islamic markets are propagated between Islamic markets. Our findings suggest that the Islamic finance industry does not seem able to provide cushion against economic and financial shocks that affect conventional markets.     

Financial crisis and stock market efficiency: Empirical evidence from Asian countries

This paper empirically investigates the effects of the 1997 financial crisis on the efficiency of eight Asian stock markets, applying the rolling bicorrelation test statistics for the three sub-periods of pre-crisis, crisis, and post-crisis. On a country-by-country basis, the results demonstrate that the crisis adversely affected the efficiency of most Asian stock markets, with Hong Kong being the hardest hit, followed by the Philippines, Malaysia, Singapore, Thailand and Korea. However, most of these markets recovered in the post-crisis period in terms of improved market efficiency. Given that the evidence of nonlinear serial dependencies indicates equilibrium deviation resulted from external shocks, the present findings of higher inefficiency during the crisis are not surprising as in the chaotic financial environment at that time, investors would overreact not only to local news, but also to news originating in the other markets, especially when the news events were adverse.     

Impact of the global financial crisis on Islamic and conventional stocks and bonds

This study explores the impact of the global financial crisis (GFC) on Islamic and conventional stock and bond indices in 11 Islamic and eight non‐Islamic countries. We find that there are benefits of Islamic stocks during the GFC, particularly during the early stage of the crisis because Islamic institutions are prohibited from holding sub‐prime mortgage securities and derivatives. The strongest benefits of Islamic stocks are in the UK and USA. We conclude that there are benefits of risk reduction and stability for Islamic stocks during a financial crisis, although not necessarily during a global recession.     

Constructing Fama–French Factors from Style Indices: Evidence from the Islamic Equity Market

This study has contributed to the analysis of the Fama–French three-factor model by proving the validity of model using the newly constructed Fama–French factors from Malaysian Islamic stock market. With generalized method of moments and robustness tests, our results compliment earlier studies by comparing the results over two sub-periods, before and after the financial crises and the fall of Lehman Bros. The results of the analysis suggest that the reversal of size effects exists after periods of financial crisis. This is the first attempt to create FF factors and test the model from Islamic equity style indices.     

Risk,return and mean‐variance efficiency of Islamic and non‐Islamic stocks: evidence from a unique Malaysian data set

We find that Islamic stocks are more mean–variance efficient than non‐Islamic stocks and the market because they reduce risk of the same level of returns. We combine a unique Malaysian data set of individual Islamic stocks (as opposed to aggregate stock indices) since 1997 with a new method where we apply Islamic business activity and financial ratio screens to the universe of Malaysian stocks. Both data sets show that Islamic stocks have an annualised standard deviation that is on average 3.43–3.78 percent points lower compared to non‐Islamic stocks. This lower variance of Islamic stocks is exclusively driven by financial ratio screens.     

Sources of Fluctuations in Islamic,U.S., EU,and Asia Equity Markets: The Roles of Economic Uncertainty,Interest Rates,and Stock Indexes

This article analyzes the economic and financial sources of fluctuations among the U.S. federal funds rates, the U.S. economic policy uncertainty, and the indices of the U.S., European, Asian, and Islamic stock markets. The impulse response analysis shows that the U.S. economic policy uncertainty shocks have significant and negative effects unanimously on the U.S., European, Asian, and Islamic stock markets. A contractionary monetary policy shock, in terms of a higher federal funds rate, has also a statistically significant and negative effect on all of the stock markets. The variance decomposition results indicate that the Islamic stock index is mainly affected by the U.S. stock index shock, thus negating its dichotomy hypothesis. The U.S. economic uncertainty shock explains an important portion of fluctuations for all four stock indices. The degree of synchronization between the EU stock market and other markets has weakened after the U.S. financial crisis.     

Islamic and conventional portfolios optimization under investor sentiment states: Bayesian vs Markowitz portfolio analysis

This paper investigates the portfolio optimization under investor’s sentiment states of Hidden Markov model and over a different time horizon during the period 2004–2016. To compare the efficient portfolios of the Islamic and the conventional stock indexes, we have employed two approaches: the Bayesian and Markowitz mean-variance. Our findings reveal that the Bayesian efficient frontier of Islamic and conventional stock portfolios is affected by the investor’s sentiment state and the time horizon. Our findings also indicate that the investor’s sentiment regimes change the Islamic and the conventional optimal diversified portfolios.Moreover, the results show that the potential diversification benefits seem to be more important when using the Bayesian approach than when applying the Markowitz approach. This finding is valid for the bearish, depressed, bullish and calm states in Islamic stock markets. However, the diversification of potential portfolios is significant only for the bullish and the bubble states in the conventional financial markets.The findings of the study provided additional evidence for investors to exploit googling investor sentiment states to evaluate the portfolio performance and make an optimal portfolio allocation.     

Impact of COVID-19 on stock market efficiency: Evidence from developed countries

This study investigates the impact of the novel coronavirus (COVID-19) pandemic on stock market efficiency for six hard-hit developed countries, namely, the United States (US), Spain, the United Kingdom (UK), Italy, France, and Germany. Applying the wild bootstrap automatic variance ratio test on daily stock market data from July 29, 2019 to January 25, 2021, it is found that all stock markets used in this study deviate from market efficiency during some periods of the pandemic. Deviations from market efficiency are seen more in the stock markets of the US and UK during the COVID-19 outbreak than in other stock markets. These results are strengthened when a different econometric method, the automatic portmanteau test, is used. The findings of this study indicate an increasing chance for stock price predictions and abnormal returns during the COVID-19 pandemic.     

The impact of religious practice on stock returns and volatility

With a psychological and behavioral perspective, this paper examines whether religious practice, through its influence on investors' moods and emotions, affect the behavior of the stock markets and investors in 15 Islamic countries over the period December 31, 2005 to December 31, 2015 and over four sub-periods (before and after both the global financial crisis and the Arab spring). The results indicate that volatility decreases during the month of Ramadan and is significantly different from the volatility observed in the other 11 months of the Islamic calendar year in most Muslim countries. We also identify that changes in stock returns and volatility during the month of Ramadan are related to religious practice and not due to the global financial crisis or the Arab spring. The findings significantly improve the understanding of the role of religious practice on stock market behavior and as such may be of great interest to investors and market regulators.     

Modelling long run comovements in equity markets: A flexible approach

International equity markets linkages are characterized by nonlinear dependence and asymmetries. We investigate shifts in long run comovements in stock markets by means of an ‘interrupted’ Markov switching cointegration specification. This flexible approach allow us to study to what extent documented changes in global integration are permanent, or whether market linkages are subject to changes. Using an illustrative sample from 1980 to 2012 for USA, UK and Hong Kong stock price indices, we find evidence of interrupted cointegration across these markets between May 1997 and April 2002, which is consistent with the decoupling of stock prices from fundamentals during the dot-com bubble.     

The changing and relative efficiency of European emerging stock markets

The martingale hypothesis is tested for 15 European emerging stock markets located in Croatia, the Czech Republic, Estonia, Hungary, Iceland, Latvia, Lithuania, Malta, Poland, Romania, Russia, the Slovak Republic, Slovenia, Turkey and the Ukraine. For comparative purposes, the developed stock markets in Greece, Portugal and the UK are also included. Rolling window variance ratio tests based on returns and signs and with wild bootstrapped p-values are used with daily data over the period beginning in February 2000 and ending in December 2009. The fixed-length rolling sub-period window captures changes in efficiency and is used to identify events which coincide with departures from weak-form efficiency and to rank markets by relative efficiency. Overall, return predictability varies widely. The most efficient are the Turkish, UK, Hungarian and Polish markets; the least efficient are the Ukrainian, Maltese and Estonian stock markets. The global financial market crisis of 2007–2008 coincides with return predictability in the Croatian, Hungarian, Polish, Portuguese, Slovakian and UK stock markets. However, not all markets were affected: the crisis had little effect on weak-form efficiency in stock markets located in Greece, Latvia, Romania, Russia and Turkey.     

Are Islamic stock indexes exposed to systemic risk? Multivariate GARCH estimation of CoVaR

The main objective of this paper is to assess the exposure of Islamic stock indexes to systemic tail events. We use Conditional Value-at-Risk (CoVaR) and Delta CoVaR measures as developed by Adrian and Brunnermeier (2011) and a sample of Islamic and conventional stock indexes, from various developed and emerging markets, during the period September 2005 to March 2015. The empirical results reveal that the systemic risk has a moderate adverse effect on Islamic indexes, with a lower level in Gulf Cooperation Council countries (GCC hereafter). The findings also show the Asian stock indexes can be considered as effective hedge assets, after the global financial crisis (GFC hereafter). Furthermore, the empirical reveal that portfolio including Islamic stock indexes performs better than a benchmark portfolio in turmoil periods. These findings have several implications in financial decisions including the strategy of stability and asset allocation.     

Granger-causality in quantiles between financial markets: Using copula approach

This paper considers the Granger-causality in conditional quantile and examines the potential of improving conditional quantile forecasting by accounting for such a causal relationship between financial markets. We consider Granger-causality in distributions by testing whether the copula function of a pair of two financial markets is the independent copula. Among returns on stock markets in the US, Japan and U.K., we find significant Granger-causality in distribution. For a pair of the financial markets where the dependent (conditional) copula is found, we invert the conditional copula to obtain the conditional quantiles. Dependence between returns of two financial markets is modeled using a parametric copula. Different copula functions are compared to test for Granger-causality in distribution and in quantiles. We find significant Granger-causality in the different quantiles of the conditional distributions between foreign stock markets and the US stock market. Granger-causality from foreign stock markets to the US stock market is more significant from UK than from Japan, while causality from the US stock market to UK and Japan stock markets is almost equally significant.     

Islamic investing

Using a large international sample of 35 developed and emerging markets, we analyze whether Islamic indices exhibit a different performance to conventional benchmarks. While there is no compelling evidence of performance differences in robust Sharpe ratio tests and after controlling for market risk, we find a significantly positive four-factor alpha for the aggregate developed markets region. This outperformance stems, however, mainly from the U.S. and is largely attributable to the exclusion of financial stocks in Sharia-screened portfolios. As the extensive downturn of financials is related to the recent financial crisis, we do not argue that this outperformance will continue over time. The style analysis reveals that Islamic indices invest mainly in growth stocks and positive momentum stocks. This, for a passive portfolio intriguing result can, however, be explained by the strong sector allocation towards energy firms and their strong momentum characteristic during the sample period.     

What Influences Stock Market Behavior in Russia and Other Emerging Countries?

We empirically test the dependence of the Russian stock market on the world stock market and world oil prices in the period 1997:10–2012:02. We also analyze countries that can be considered to be relatively similar to Russia, e.g., Poland, the Czech Republic, and South Africa. First, we apply a rolling regression to identify periods when oil prices or stock indices in the United States and Japan were important. Surprisingly, oil prices are not significant for the Russian stock market after 2006. Second, we employ a TGARCH-BEKK model to assess the degree of correlation between the markets in question, taking into account the global market stochastic trend. Correlation between markets increased between 2000 and 2012.     

Exchange-rate return predictability and the adaptive markets hypothesis: Evidence from major foreign exchange rates

This study examines return predictability of major foreign exchange rates by testing for martingale difference hypothesis (MDH) using daily and weekly nominal exchange rates from 1975 to 2009. We use three alternative tests for the MDH, which include the wild bootstrap automatic variance ratio test, generalized spectral test, and Dominguez–Lobato consistent tests. We evaluate time-varying return predictability by applying these tests with fixed-length moving sub-sample windows. While exchange rate returns are found to be unpredictable most of times, we do observe a number of episodes of statistically significant return predictability. They are mostly associated with the major events such as coordinated central bank interventions and financial crises. This finding suggests that return predictability of foreign exchange rates occurs from time to time depending on changing market conditions, consistent with the implications of the adaptive markets hypothesis.     

Volatility and correlation of Islamic and conventional indices during crises

We examine the correlation and volatility of Islamic indices and their conventional counterparts during the 2008–2009 Global Financial Crisis as well as the Covid-19 pandemic. We provide evidence that the volatility of Islamic indices is relatively lower than that of conventional peers during turmoil periods. Consistent with the decoupling hypothesis, our results indicate that the volatility of Islamic and the volatility of conventional indices tend to move in tandem in tranquil times but diverge in times of crises. Our results also indicate that the correlation between Islamic and conventional indices is a priced risk factor for Islamic index returns.