This paper examines mean reversion processes in volatility structure of stock markets after extremely high or low stock returns. The stock market volatility is reflected in three aspects, overall volatility, volatility momentum, and volatility concentration, and they are measured by three basic...

This paper analyses the possible effects of the Covid-19 pandemic on the degree of persistence of US monthly stock prices and bond yields using fractional integration techniques. The model is estimated first over the period January 1966-December 2020 and then a recursive approach is taken to...