In this paper we investigate the volatility structure of the German stock market index DAX and its constituents. Using a recently developed test, we find a volatility break in 1997. Interestingly, not only is the volatility higher after 1997 but the volatility persistence also increased. That...

This paper investigates the regional differences in the spread of COVID-19 infections in Germany. A machine learning selection procedure is used to reduce variables from a pool of potential influencing variables. The empirical analysis shows that both regional structural variables and regionally...

In this paper we introduce and test the hypothesis that the relation between inflation and unemployment has been in many countries subject to a significant change in the early 1990's after the disinflation period. That period began between 1975 and 1980 after the first (or the second) oil price...