Techniques for testing the null hypothesis of difference stationarity against stationarity around some deterministic function have received much attention. In particular, unit root tests where the alternative is stationarity around a smooth transition in a linear trend have recently been...

Systems of economic data potentially exhibit a number of common features, which aid both econometric modelling and economic interpretation. This paper surveys a variety of common features and applies the corresponding testing and estimation techniques to systems of macroeconomic time series in...