This paper provides a continuous record interpretation of the block local to unity asymptotics proposed recentlyby Phillips, Moon and Xiao (2001). It also demonstrates that in the case of homogeneous dynamics and a fixednumber of blocks, the new asymptotic approximation coincides with the...

This paper considers tests for a unit root when the innovations follow a near-integrated GARCH process. We compare the asymptotic properties of the likelihoodratio statistic with that of the least-squares based Dickey-Fuller statistic. We first useasymptotics where the GARCH variance process is...