Purchasing power parity: Evidence from developing countries

This paper utilizes the dynamic error-correction model (DECM) to examine the issue of purchasing power parity (PPP) for 11 developing countries (Argentina, Bolivia, Colombia, Cote ďlvoire, Ecuador, Guatemala, Kenya, Nigeria, Peru, South Africa, and Venezuela). For comparison purposes, evidence from the traditional unit root methods of the augmented Dickey-Fuller (ADF) and Phillips-Perron is presented. The results from the conventional unit root tests failed to find evidence of PPP in all of the cases. However, the results from the generalized error-correction model detected evidence of PPP for nine out of the 11 countries under consideration. Based on these results, it was concluded that PPP holds in the long-run for the sample countries and that the implicit restrictions associated with unit root tests prevented earlier studies from finding evidence in support of PPP theory. (JEL F31).