In this paper the seasonal unit root test of Hylleberg et al. (1990) is generalized to cover a heterogenous panel. The procedure follows the work of Im, Pesaran and Shin (2002). Test statistics are proposed and critical values are obtained by simulations. Moreover, the properties of the tests...

We analyze daily changes of two log foreign exchange (FX) rates involving the Deutsche Mark (DEM) for the period 1975 - 1998, namely FX-rates measured against the US dollar (USD) and the Japanese yen (JPY). Ta account for volatility e1ustering we fit a GARCH(l,l)-model with leptokurtic...

In this paper we test the purchasing power parity for the post Bretton Woods period for 18 main industrial countries. As base currencies we use alternatively the Deutsche mark, the Japanese yen, and the US dollar. We employ error correction models for single countries and on the level of pooled...