Polynomial specifications are widely used, not only in applied economics, but also in epidemiology, physics, political analysis and psychology, just to mention a few examples. In many cases, the data employed to estimate such specifications are time series that may exhibit stochastic...

This paper tests if air pollution serves as a carrier for SARS-CoV-2 by measuring the effect of daily exposure to air pollution on its spread by panel data models that incorporates a possible commonality between municipalities. We show that the contemporary exposure to particle matter is not the...

We propose a multi-level dynamic factor model to represent the commonalities in the hourly evolution of realized volatilities of several exchange rates. The model assumes a global factor active during the twenty-four hours of the day, plus four intermittent factors, associated with markets...