Testing for PPP in developing countries using confirmatory analysis and different base countries: an application to Asian countries

Previous studies on PPP have tested either the null hypothesis of non-stationary or the null of a stationary real exchange rate and used the US as the base country and focused on industrialized countries. It has been argued that testing either null is insufficient to confirm the presence of PPP. It has also been noticed that the results are sensitive to the choices of the base country; for instance, the US versus Germany. In contrast to previous studies, this paper uses different unit root tests, confirmatory analysis, and different base countries to test PPP for a sample of developing countries in Asia during the current float. Overall, the results do not seem to be sensitive to the choice of the base country, and joint rejections are not present but joint non-rejections are far more common. Using Perron's test, which allows for a one-time break in the series, the results indicate evidence of stationarity for Indonesia, Korea, Malaysia and Thailand when the US is the base country. When Japan is the base country, evidence of stationarity is detected only for Indonesia.