Does COVID-19 open a Pandora's box of changing the connectedness in energy commodities?

Time-frequency volatility transmission among energy commodities and financial markets during the COVID-19 pandemic: A Novel TVP-VAR frequency connectedness approach

This paper investigates the dynamic volatility spillover among energy commodities and financial markets in pre-and mid-COVID-19 periods by utilizing a novel TVP-VAR frequency connectedness approach and the QMLE-based realized volatility data. Our findings indicate that the volatility spillover is mainly driven by long-term components and prominently time-varying with a remarkable but short-lived surge during the COVID-19 outbreak. We further spot that WTI and NGS are prevailingly transmitting and being exposed to the system volatility simultaneously, especially during the global pandemic, suggesting the energy commodity market becoming more integrated with, more influential and meanwhile vulnerable to global financial markets.

The role of the COVID-19 pandemic in time-frequency connectedness between oil market shocks and green bond markets: Evidence from the wavelet-based quantile approaches

This study contributes to the existing literature on the relationship between oil market shocks and the green bond market by investigating the impact of the COVID-19 pandemic on their dynamic correlation. We first decompose the oil market shocks into components using a time-frequency framework. Then, we combine wavelet decomposition and quantile coherence and causality methods to discuss changes during the COVID-19 era. We observe positive effects of both supply-driven and demand-driven oil shocks on the green bond market at most quantile levels. However, supply-driven oil price changes play a major role. The results also indicate that long-term changes have a greater impact than short-term changes on the connection between oil and green bond markets. Nevertheless, the COVID-19 pandemic changed the nature of the causal relationship, as we observed no relationship under extreme market conditions during the pandemic era. We argue that the economic and social impacts of the COVID-19 pandemic have left investors focusing on the short-term substitution between oil and green bond markets.

Global energy markets connectedness: evidence from time-frequency domain

We examine the presence of dependence across 51 energy markets classified into different regions from Jan 2007 to June 2021. In order to examine the presence of dependence across different energy markets, we apply standard and threshold dependence measures proposed by Diebold and Yilmaz, Int J Forecast 28:57-66, (2012) and Baruník and Křehlík, J Financ Econ 16(2):271-296, (2018). We highlight the presence of strong dependence between the energy markets at both regional level and across other regions. European and American energy markets are highly connected within the region over the long-run whereas Asia-Pacific and the African energy markets offer optimal diversification opportunities. Both short- and long-run dependence exists between Chinese and the Hong Kong energy markets and between the US and Canadian energy markets. We also witness substantial increase dependence across all the energy markets during different crisis periods.

Extreme spillover effect of COVID-19 pandemic-related news and cryptocurrencies on green bond markets: A quantile connectedness analysis

We provide the first empirical study on the role of panic and stress related to the COVID-19 pandemic, including six uncertainties and the four most traded cryptocurrencies, on three green bond market volatilities. Based on daily data covering the period from January 1, 2020 to January 31, 2022, we combine Diebold and Yilmaz's (2012, 2014) time domain spillover approach and Ando et al.'s (2022) quantile regression framework to investigate the time-frequency spillover connectedness among markets and measure the direction and intensity of the net transmission effect under extreme negative and positive event conditions, and normal states. We further provide novel insights into the green finance literature by examining sensitivity to quantile analysis of the net transfer mechanism between green bonds, cryptocurrencies, and pandemic uncertainty. Regarding the network connectedness analysis, the results reveal strong net information spillover transmission among markets under the bearish market. In extremely negative event circumstances, the MSCI Euro green bond acts as the leading net shock receiver in the system, whereas COVID-19 fake news appears as the largest net shock contributor, followed by BTC. According to sensitivity to quantile analysis, the net dynamic shock transfer mechanism is time-varying and quantile-dependent. Overall, our work uncovers crucial implications for investors and policymakers.

COVID-19 and adaptive behavior of returns: evidence from commodity markets

This study examines the Adaptive Market Hypothesis during the COVID-19 pandemic. The pandemic has impacted global economic activity, trade, and financial market activity. There has been much interest in testing financial market theories and relationships during COVID-19. Therefore, we have investigated the varying return predictability from commodities during COVID-19 concerning the adaptive market hypothesis. By applying linear and non-linear econometric models, we find a strong engagement of adaptive behavior of returns from commodities during the ongoing pandemic. The inconsistent return behavior is facilitated by dividing the sample period into different phases. Our results indicate that AMH best explains the impact of COVID-19 on commodity markets.

Time-frequency connectedness between energy and nonenergy commodity markets during COVID-19: Evidence from China

We aim to investigate the static and dynamic time-frequency connectedness between energy and nonenergy commodity markets in China during COVID-19 based on Baruník and Křehlík (2018) method. First, in this paper, we find that the short-term connectedness dominates the long-term one, and the total connectedness increases after the COVID-19 outbreak. Second, the energy commodity is the receiver and is influenced much by the spillovers of non-energy commodity markets (e.g. chemical commodities and non-ferrous metals) in the short run. At the same time, the impact is less at the long-term investment horizons. In addition, chemical commodities and soft commodities are the primary transmitters in this system in the short run. In contrast, chemical commodities and coal steel iron commodities are the main long-run primary transmitters. Third, the spillover role varies with the time-frequency domain during COVID-19. To be more specific, the energy commodity shows a net receiver role in the short and long run before the COVID-19 pandemic, but after it, the role of the net transmitter can be seen in the long run with ease. Finally, we show that COVID can reduce the hedging effectiveness at different investment horizons. The mineral policymakers should note our dynamic empirical results between energy and nonenergy commodity.

Rethinking financial contagion: Information transmission mechanism during the COVID-19 pandemic

Rapidly growing numbers of empirical papers assessing the financial effects of COVID-19 pandemic triggered an urgent need for a study summarising the existing knowledge of contagion phenomenon. This paper provides a review of conceptual approaches to studying financial contagion at four levels of information transmission: (i) Catalyst of contagion; (ii) Media attention; (iii) Spillover effect at financial markets; (iv) Macroeconomic fundamentals. We discuss the unique characteristics of COVID-19 crisis and demonstrate how this shock differs from previous crises and to what extent the COVID-19 pandemic can be considered a ‘black swan’ event. We also review the main concepts, definitions and methodologies that are frequently, but inconsistently, used in contagion literature to unveil the existing problems and ambiguities in this popular area of research. This paper will help researchers to conduct coherent and methodologically rigorous research on the impact of COVID-19 on financial markets during the pandemic and its aftermath.

The impact of government interventions on cross-listed securities: Evidence from the COVID-19 pandemic

This paper examines the impact of COVID-19 related governments' interventions on the volatility and liquidity of American depository receipts (ADRs). Using a wide dataset of 387 ADRs from 34 countries around the globe, we provide an examination of the effect of economic and non-economic interventions on the quality of these cross-listed securities. Our results suggest that closures, restrictions, as well as containment health steps implemented during the outbreak period of the pandemic, seem to deteriorate the ADRs' liquidity and stability. The negative impact holds for different control variables and regression specifications and is not subsumed by the inclusion of the daily confirmed cases as a proxy for the severity of the pandemic. The information documented here may assist financial market participants in their risk management. The findings could also be important for policymakers for their preparedness plans in case of future crises.

Impact of COVID-19 on the quantile connectedness between energy, metals and agriculture commodities

With many studies highlighting the heterogeneous impact of the COVID-19 pandemic on different commodity markets, this study provides evidence of quantile connectedness between energy, metals, and agriculture commodity markets before and during the COVID-19 outbreak. Since mean-based measures of connectedness are not necessarily suitable to measure connectedness in the crisis period, especially in the tails of the return distribution, thus in this study, we use the newly developed approach of quantile-based connectedness. The full-sample analysis results show that return shocks only propagate within the energy commodity group. The findings manifest that transmission of return spillovers is stronger in the left and right tails of the conditional return distribution. In addition, the results unveil that degree of tail-dependence between energy, metals, and agriculture commodities are time-varying. Meanwhile, our sub-sample analysis clearly shows that the commodity market return connectedness demonstrates a significant shift over time due to COVID-19 shocks. There is evidence of strong transmission of return shocks between energy, metals, and agriculture commodities during the COVID-19 fiasco. Finally, the results also illustrate that softs and livestock commodities hold significant diversification benefits for energy market investors.

Did the COVID-19 pandemic (really) positively impact the IPO Market? An Analysis of information uncertainty

Anecdotal evidence seems to suggest that the initial public offering (IPO) market performed remarkably well through the COVID-19 pandemic. To further understand this peculiar observation, we carry out a comprehensive analysis of IPOs during the pandemic vis-a-vis IPOs before the pandemic. Our findings imply that IPOs during the pandemic experience greater information uncertainty compared to those before the pandemic, and this greater uncertainty is mainly driven by the IPOs from the high-technology and the healthcare sectors. Furthermore, we find that an average IPO firm experiences larger underpricing and more post-IPO return volatility as the pandemic and the associated government responses increase in severity before the offering. Overall, our study indicates that the COVID-19 pandemic had an adverse impact on the IPO market.

Time-frequency volatility spillovers between major international financial markets during the COVID-19 pandemic

We examine volatility spillovers and their time-frequency dynamics among major global financial markets from the outbreak of COVID-19 to present. Results show that total spillovers, driven by low frequency components, peaks at the end of March 2020 and then decline, which is not consistent with the upward trend of COVID-19; Stock markets of US and UK are net spillover transmitters, while other markets are net spillover receivers. The findings suggest that markets rally in the short term, but investors need to beware of bubbles and liquidity tightening expectations, and policymakers can gradually start to resume conventional monetary policy.

Is ESG Relevant to Electricity Companies during Pandemics? A Case Study on European Firms during COVID-19

The electricity sector was negatively impacted by the coronavirus disease (COVID-19), with considerable declines in consumption in the initial phase. Investors were in turmoil, and stock prices for these companies plummeted. The aim of this paper is to demonstrate the significant negative influence of the pandemic on abnormal returns for the electricity sector, specifically for traditional and renewable companies and the influence of ESG scores, using the event study approach and multi-variate regressions. Our results show that the pandemic indeed had a negative impact on the electricity sector, with renewable electricity companies suffering a sharper decline than traditional ones. Moreover, we find that ESG pillar scores affected electricity companies differently and are sector-specific. For renewable electricity companies, the returns were positively influenced by the environmental ESG scores and negatively by governance ESG scores.

Dependence dynamics of Islamic and conventional equity sectors: What do we learn from the decoupling hypothesis and COVID-19 pandemic?

The recent COVID-19 pandemic intensification generates a different set of challenges for global financial markets and portfolio management strategies. This paper uses network analysis to investigate the static and dynamic dependence within Islamic and conventional equity sectors. The study focuses on the decoupling hypothesis and how the dependence among sectors changes during COVID19. Empirical findings indicate a higher degree of spillover during the COVID19 sub-period. Islamic and conventional equities behave differently in terms of industry-level dependence during normal and crisis times, thus decoupling. Further, the dependence effect between conventional equity returns is stronger than Islamic equity returns during the COVID-19 pandemic. The finding of this paper has several significant implications for portfolio selection and risk management. Portfolios consisting of Islamic equity sectors including industrials, basic materials, consumer services, and technologies highlight low-diversification benefits across the entire sample period. Also, investment exposure to less connected Islamic and conventional equity sectors provides a good diversification strategy.

Contagion and portfolio management in times of COVID-19

This paper aims to investigate the COVID-19 pandemic impacts on the interconnectedness between the Chinese stock market and major financial and commodity markets-gold, silver, Bitcoin, WTI, S&P 500, and Euro STOXX 50-and analyze the portfolio design implications. Using daily data from 2018 to 2021, we first apply the wavelet power spectrum (WPS) to visualize volatility shifts. In contrast to previous research, we empirically identify the precise COVID-19 outbreak dates for each market using the Perron (1997) breakpoint test. Finally, we employ the bivariate DCC-GARCH model to analyze the connectedness between markets. The findings reveal that the COVID-19 pandemic caused volatility shifts of different intensities for all of the studied markets. Moreover, each return series exhibits one break date, which is specific to each market and corresponds to a distinct COVID-19-related event. Correlations, hedge ratios, and optimal portfolio weights changed significantly after the COVID-19 outbreak. There is evidence of contagion effects between the Chinese stock market and S&P 500, Euro STOXX 50, gold, and silver. Interestingly, the latter two assets lost their safe haven property with SSE. However, WTI and Bitcoin act as safe havens against SSE risks.

Impact of COVID-19 outbreak on multi-scale asymmetric spillovers between food and oil prices

This paper analyzes the time-frequency spillover effects between food and crude oil markets, two particularly important commodity markets, under the impact of the pandemic. Using the BK frequency domain spillover index and the rolling window method, we explore the spillover effects between the food and crude oil markets under the influence of COVID-19, and compare the changes of spillover effects in each market before and during the pandemic. Based the network connectedness method and the Bayesian structural time series method, we further reveal the changes of the pairwise spillover effects between markets on different time scales. Our study shows that the food-oil market system has the strongest spillover effect in the short term, and the spillovers during the pandemic are significantly weaker than that under the financial crisis. In addition, the pandemic has significantly increased the impact of corn on the crude oil market, but reduced its spillovers on soybeans and rice. Finally, during the COVID-19 period, the wheat market is likely to receive more spillovers from other markets, particularly corn and soybeans. These findings are of great significance for market participants with different horizons to understand the spillover effects of food and oil markets under the impact of the pandemic and to avoid the risk transmission across markets or assets.

The Time-Varying Connectedness Between China's Crude Oil Futures and International Oil Markets: A Return and Volatility Spillover Analysis

This paper examines the relationship between world crude oil markets following the introduction of Shanghai crude oil futures from the perspective of network connectedness based on the vector autoregressive model. The connectedness measurement method proposed by Diebold and Yilmaz (Econ J 119(534):158-171, 2009, Int J Forecast 28(1):57-66, 2012. 10.1016/j.ijforecast.2011.02.006, J Econom 182(1):119-134, 2014. 10.1016/j.jeconom.2014.04.012) is adopted to study a time-varying interdependence relationship. The empirical results show that the world crude oil markets exhibit a high degree of integration from both returns and volatility; however, the direction and magnitude contributed by each market varies significantly. Specifically, the West Texas Intermediate futures and Brent spot and futures markets were found to have the highest contributions to the world oil market over the entire sample period and take leading roles, whereas Dubai futures market was found to be the most important receiver, and has received the most spillover from other markets and passed it throughout the system. Shanghai crude oil futures is not yet highly connected with other markets. Moreover, heterogeneous changes in the direction, intensity, and persistence of the spillover were observed across markets after the outbreak of the COVID-19 pandemic in 2020. This study reveals the integration level of Shanghai crude oil futures and the dynamics of linkages between regional crude oil markets, which is of great significance for market participants, policymakers, and future researchers.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12076-021-00288-z.

Analysis of the impact of COVID-19 pandemic on G20 stock markets

We examine the impact of the COVID-19 pandemic on G20 stock markets from multiple perspectives. To measure the impact of COVID-19 on cross-market linkages and deeply explore the dynamic evolution of risk transmission relations and paths among G20 stock markets, we statically and dynamically measure total, net, and pairwise volatility connectedness among G20 stock markets based on the DY approach by Diebold and Yilmaz (2012, 2014). The results indicate that the total volatility connectedness among G20 stock markets increases significantly during the COVID-19 crisis, moreover, the volatility connectedness display dynamic evolution characteristics during different periods of the COVID-19 pandemic. Besides, we also find that the developed markets are the main spillover transmitters while the emerging markets are the main spillover receivers. Furthermore, to capture the impact of COVID-19 on the volatility spillovers of G20 stock markets, we individually apply the spatial econometrics methods to analyze both the direct and indirect effects of COVID-19 on the stock markets’ volatility spillovers based on the “volatility spillover network matrix” innovatively constructed in this paper. The empirical results suggest that stock markets react more strongly to the COVID-19 confirmed cases and cured cases than the death cases. In general, our study offers some reference for both the investors and policymakers to understand the impact of COVID-19 on global stock markets.

Risk transmission from the COVID-19 to metals and energy markets

We examine the risk transmission from the COVID-19 to metal (precious and industrial) and energy markets using the BEKK-MGARCH model. The findings reveal the significant and negative volatility transmission from the COVID-19 to gold, palladium, and brent oil markets, suggesting the safe-haven properties of these markets. The COVID-19 risk is not transmitted to the industrial metal market, whereas the rise in COVID-19 volatility leads to an increase in WTI oil market volatility. These results provide useful insights to investors and policymakers regarding risk management, asset pricing, and financial market stability during the COVID-19 pandemic.

The Connections between COVID-19 and the Energy Commodities Prices: Evidence through the Dynamic Time Warping Method

The main objective of the study is to assess the similarity between the time series of energy commodity prices and the time series of daily COVID-19 cases. The COVID-19 pandemic affects all aspects of the global economy. Although this impact is multifaceted, we assess the connections between the number of COVID-19 cases and the energy commodities sector. We analyse these connections by using the Dynamic Time Warping (DTW) method. On this basis, we calculate the similarity measure—the DTW distance between the time series—and use it to group the energy commodities according to their price change. Our analysis also includes finding the time shifts between daily COVID-19 cases and commodity prices in subperiods according to the chronology of the COVID-19 pandemic. Our findings are that commodities such as ULSD, heating oil, crude oil, and gasoline are weakly associated with COVID-19. On the other hand, natural gas, palm oil, CO2 allowances, and ethanol are strongly associated with the development of the pandemic.

Price overreactions in the commodity futures market: An intraday analysis of the Covid-19 pandemic impact

The objective of this paper is to examine the overreaction behavior of 20 commodity futures based on intraday data from November 20, 2019 to June 3, 2020 with a focus on the impact of the Covid-19 pandemic. A dynamic and non-parametric approach is applied on intraday data for four different frequencies (from 1 min to 1 h) and two different sub-periods (pre-Covid-19 pandemic and during Covid-19 pandemic) in order to detect overreaction behavior which is defined as a large change of prices followed by proportional price reversals. Our empirical findings show that the overreaction hypothesis is confirmed for the considered commodity futures. Furthermore, both the number and the amplitude of overreactions is higher during the Covid-19 pandemic. Our findings also indicate that soft and metal commodities show much less overreactions than precious metals and especially energy commodities. In particular, crude oil futures exhibit a different overreaction behavior compared to other commodities since it has a higher number of negative than positive overreactions during the Covid-19 pandemic. We also find that the data frequency is independent of the overreacting behavior in both periods as the results continuously improve when having more observations due to higher frequencies. Finally, we find that extreme overreactions during the Covid-19 pandemic provide a great potential for profitable trading returns, which can be exploited by traders.