Testing for a unit root in a series obtained by summing a stationary MA(1) process with a parameter close to -1 leads to serious size distortions under the null, on account of the near cancellation of the unit root by the MA component in the driving stationary series. The situation is analysed...

Test for unit root based in wavelets theory is recently defined (Genay and Fan, 2007). While the new test is supposed to be robust to the initial value, we bring out by contrast the significant effects of the initial value in the size and the power. We found also that both the wavelets unit root...

This paper o¤ers to investigate both the Friedman's and Mishkin's hypotheses on the consequences of inflation on output growth. To this end, we first base these hypotheses in a unified framework. Second, in an empirical work based on OECD countries, we distinguish between short-medium and long...

This paper aims to provide a unified theoretical framework of the two hypotheses proposed by Friedman: (i). increased variability of money supply results in the decline of income velocity of money and (ii) high inflation leads high variability of inflation which reduces potential output growth....

Financial market participants and policy-makers can benefit from a better understanding of how shocks can affect volatility over time. This study assesses the impact of structural changes and outliers on volatility persistence of three crude oil markets - Brent, West Texas Intermediate (WTI) and...