While panel unit root tests have been used to investigate a wide range of macroeconomic issues, the tests suffer from low power to reject the unit root null in panels of stationary series if the panels consist of highly persistent series, contain a small number of series, and/or have series with...

Recently, Taylor (2002) concludes that long run PPP held over the 20th century for a set of 19 long term real exchange rates. We argue that this conclusion is quite sensitive to the use of sub-optimal lag selection in unit root tests. Using superior lag selection methods,we find that long run...

Using median-unbiased estimation, recent research has questioned the validity of Rogoff’s “remarkable consensus” of 3-5 year half-lives of deviations from PPP. These half-life estimates, however, are based on estimates from regressions where the resulting unit root test has low power. We...

We investigate convergence towards Purchasing Power Parity (PPP) within the Euro Zone and between the Euro Zone and its main partners using panel data methods that incorporate serial and contemporaneous correlation. We find strong rejections of the unit root hypothesis, and therefore evidence of...

Using median-unbiased estimation, recent research has questioned the validity of Rogoff’s “remarkable consensus” of 3-5 year half-lives of deviations from PPP. These half-life estimates, however, are based on estimates from regressions where the resulting unit root test has low power. We...