Nonlinearity and time-variation in the monetary model of exchange rates

In this paper we analyze the existence of nonlinear relationships between macroeconomic fundamentals and exchange rates for some major industrialized countries using an error correction model with time-varying parameters for the post Bretton Woods period. We find that inflation rate differentials with respect to the US inflation rate are the driving forces for the nonlinear relationships in the monetary model for exchange rates for the data from Germany, the UK, Canada, France and Italy. In addition to the variables in the traditional monetary model, also the relative interest rates are relevant in determining exchange rate changes only when the inflation differentials are either very large or very small. In contrast to previous studies we find significant long-run effects in the error correction representation of the monetary model for exchange rates when the nonlinear dynamics is taken into account in the analysis.