"Crisis" or "opportunity"? COVID-19 pandemic's impact on environmentally sound invention efficiency in China.

Introduction: The environmentally sound invention (ESI) is a "bridge" between environmental sound technologies (ESTs) and green productions. This study investigates the COVID-19 pandemic's impact on ESI efficiency using a multi-methods model in three stages. Methods: The ESI efficiency is measured using the Slack-Based Measure (SBM) method in the first stage. By excluding the environmental effect of the pandemic on each province using the stochastic frontier analysis (SFA) model's results in the second stage, this study compares the ESI efficiency change with or without the influence of the pandemic in the third stage. Results: The results show that the pandemic can be a "crisis" in the short term, but an "opportunity" in the long term. First, the SBM efficiency results in the first stage show a decrease in the number of the average efficient provinces in which the pandemic is more severe during 2020-2021. Second, results of the spatial Tobit and SFA models provide evidence that the COVID-19 pandemic negatively impacts the ESI efficiency during 2020, this impact is decreasing in 2021, and this impact has a spatial diffusion effect. Discussion: Based on these results, this study discussed the theoretical and political implications. This paper enriches the knowledge of ESTs research and development by proposing a three-stage approach with multi-methods to investigate the influence of the pandemic's impact on ESI efficiency.

"Crisis” or "opportunity”? COVID-19 pandemic's impact on environmentally sound invention efficiency in China

Introduction The environmentally sound invention (ESI) is a "bridge” between environmental sound technologies (ESTs) and green productions. This study investigates the COVID-19 pandemic's impact on ESI efficiency using a multi-methods model in three stages. Methods The ESI efficiency is measured using the Slack-Based Measure (SBM) method in the first stage. By excluding the environmental effect of the pandemic on each province using the stochastic frontier analysis (SFA) model's results in the second stage, this study compares the ESI efficiency change with or without the influence of the pandemic in the third stage. Results The results show that the pandemic can be a "crisis” in the short term, but an "opportunity” in the long term. First, the SBM efficiency results in the first stage show a decrease in the number of the average efficient provinces in which the pandemic is more severe during 2020-2021. Second, results of the spatial Tobit and SFA models provide evidence that the COVID-19 pandemic negatively impacts the ESI efficiency during 2020, this impact is decreasing in 2021, and this impact has a spatial diffusion effect. Discussion Based on these results, this study discussed the theoretical and political implications. This paper enriches the knowledge of ESTs research and development by proposing a three-stage approach with multi-methods to investigate the influence of the pandemic's impact on ESI efficiency.

COVID-19 and risk spillovers of China's major financial markets: Evidence from time-varying variance decomposition and wavelet coherence analysis.

COVID-19 has influenced financial markets drastically; however, this influence has received little attention, particularly in China. This study investigates risk spillovers across China's financial and shipping markets through dynamic spillover measures based on time-varying parameter vector autoregression and generalized forecast error variance decompositions. Stock, fund, and futures markets are identified as major risk senders, whereas other markets are identified as major risk receivers. Surprisingly, bonds, gold, and shipping are safe havens that facilitate portfolio optimization. Furthermore, using wavelet coherence analysis, we find that the coherence between dynamic total spillover and COVID-19 varies across time and frequency domains.

How the COVID-19 Pandemic Impacts Green Inventions: Evidence from a Quasi-Natural Experiment in China

This paper investigates whether the COVID-19 (coronavirus disease 2019) pandemic affects the green inventions of firms, universities, and firm–university collaborations (FUCs) differently. Our identification used provincial-level monthly data from China. Results from the difference-in-differences (DID) model showed that the COVID-19 pandemic has prompted the output of three types of green invention patents. After the parallel-trend test, placebo test, and triple-difference estimation, our conclusion has good robustness. However, the COVID-19 pandemic also influences the role of other policies, such as the SO2-emissions-trading pilot policy for universities' green inventions. There has been a slight change in the effect of dual carbon targets on green inventions since the start of the pandemic. The positive effect of the COVID-19 pandemic has been weaker for provinces where the pandemic has been more severe than in other provinces. The results of this study are compared with the results and empirical evidence of other related studies and the theoretical logic of COVID-19 crisis-promoted green inventions are discussed.

Time-frequency volatility spillovers across the international crude oil market and Chinese major energy futures markets: Evidence from COVID-19

This study investigates the impact of the recent COVID-19 pandemic on the time-frequency volatility spillovers across the international crude oil market and Chinese major energy futures markets. In addition to the Chinese crude oil market, six other major energy futures markets in China are also considered. Volatility spillover networks are constructed based on the generalized forecast error variance decomposition in the frequency domain. The results demonstrate that the outbreak of COVID-19 strengthened the total volatility spillover across these markets. Interestingly, the volatility spillovers from the international crude oil market to China's markets were found to be overall strong in the long term and to have increased substantially during the pandemic. However, the spillovers across the domestic markets were found to dominate in the short term, even with the occurrence of the pandemic and crude oil price turbulence. The findings suggest that policymakers and investors should be cautious about the diverse impacts of the pandemic at multiple scales.