1. Department of Economics and Business EconomicsAarhus University Fuglesangs Allé 4, 8210 Aarhus V Denmark
2. Center for Research in Econometric Analysis of Time Series (CREATES)Aarhus University Fuglesangs Allé 4, 8210 Aarhus V Denmark
3. Department of EconomicsUniversity at Albany, State University of New York 1400 Washington Avenue, Albany NY 12222 USA
4. Department of MathematicsImperial College London South Kensington Campus London SW7 2AZ UK