A recent article (Tse, 1998) published in this journal analysed the conditional heteroscedasticity of the yen-dollar exchange rate based on the fractionally integrated asymmetric power ARCH model. In this paper, we present replication results using Tse's (1998) yen-dollar series. We also examine the robustness of Tse's (1998) findings across different currencies, sample periods and non-nested GARCH-type models. Unlike Tse (1998), we find some evidence of asymmetric conditional volatility for daily returns of currencies measured against the dollar or the yen.