Exponential smooth transition autoregressive (ESTAR) models have been widely used in the empirical international finance literature. We show that the exponential function used in ESTAR models is ill-suited as a regime weighting function because of two undesirable properties. The first is that it...

Exponential smooth transition autoregressive (ESTAR) models are widely used in theinternational finance literature, particularly for the modelling of real exchange rates. Weshow that the exponential function is ill-suited as a regime weighting function because oftwo undesirable properties....