Are there bubbles in Chinese RMB–dollar exchange rate? Evidence from generalized sup ADF tests

This article uses recently developed generalized sup ADF (GSADF) unit root tests into the analysis of nominal RMB–dollar exchange rates bubbles. Based on the results from the GSADF tests, we find strong evidence of explosive behaviour in the nominal exchange rate and investigate two bubbles there. The first bubble is during 2005–2006 which is determined neither by the relative prices of traded goods nor the relative price of nontraded goods. The second bubble busts in 2008 during subprime crisis period, and which is determined by the relative prices of traded goods but not the relative price of nontraded goods. There is no bubble before 2005 as the exchange rate is under fixed regime. As for this result, some expansionary monetary and fiscal policies are required in China since these are the most efficient and effective under a bubble burst scenario.