In this article we re-examine efficiency of the South Korea's stock market, extending recent work of Narayan and Smyth (2004). For this purpose we apply the nonlinear unit root test procedure recently developed by Kapetanios et al. (2003). The nonlinear unit root test rejects the null hypothesis...

The validity of Purchasing Power Parity (PPP) is re-examined using data for some emerging market economies and African countries, extending recent works of Doğanlar <italic>et al.</italic> (2009) and Chang <italic>et al.</italic> (2010), respectively. For this purpose, we apply new unit root tests that allow for nonlinearities...