This paper discusses a number of likelihood ratio tests on long-run relations and common trends in the I(2) model and provide new results on the test of overidentifying restrictions on beta xt and the asymptotic variance for the stochastic trends parameters, alpha 1: How to specify deterministic...

It is well known that if X(t) is a nonstationary process and Y(t) is a linear function of X(t), then cointegration of Y(t) implies cointegration of X(t). We want to find an analogous result for common trends if X(t) is generated by a finite order VAR. We first show that Y(t) has an infinite...

The notions of instrument, intermediate target and final target are defined in the context of the cointegrated VAR. A target variable is said to be controllable if it can be made stationary around a desired target value by using the instrument. This can be expressed as a condition on the...

Asset prices undergo long swings that revolve around benchmark levels. In currency markets, fluctuations involve real exchange rates that are highly persistent and that move in near-parallel fashion with nominal rates. The inability to explain these two regularities with one model has been...

Two methodological approaches to empirical economics which are labelled 'theory first' versus 'reality first' are introduced building the background for the discussion of the individual contributions to this special issue. --