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COVID-19 and financial market efficiency: Evidence from an entropy-based analysis
Jingjing Wang1, Xiaoyang Wang1
1Jingjing Wang and Xiaoyang Wang are both assistant professor in the Department of Economics at the University of New Mexico, Albuquerque, United States.
Abstract:
This study assesses the market efficiency of S&P 500 Index, gold, Bitcoin and US Dollar Index during the extreme event of COVID-19 pandemic. Market efficiency is estimated by a multiscale entropy-based method for the scales of hourly and 1 to 30 business days. At all scales, four markets' efficiency decreases sharply and persistently during February-March 2020. Market efficiency decreases the most in S&P 500 Index and the least in Bitcoin market. Bitcoin market efficiency is more resilient than others during the extreme event, which is an attractive feature to serve as a safe haven asset.
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