Juselius, Katarina - In: Economics: The Open-Access, Open-Assessment E-Journal 8 (2014) 2014-21, pp. 1-30
Researchers seldom find evidence of I(2) in exchange rates, prices, and other macroeconomics time series when they test the order of integration using univariate Dickey-Fuller tests. In contrast, when using the multivariate ML trace test they frequently find double unit roots in the data. The...