Searching stationarity in the real exchange rates: Application of the SUR estimator

In the foreign exchange market, all national currencies are priced in terms of a common numeraire (usually the U.S. dollar); hence, cross-currency correlation is likely to be important in the empirical investigation of stationarity. Recently, the SUR estimator is employed to account for the effects of cross-currency correlation on the long-run purchasing power parity. Under the SUR framework, this paper examines the joint unit-root null and the ADF-based panel unit root. Data of 30 currencies, spans from 1980 to 1999, are used for empirical analysis and the results are supportive.