'Classical' econometric theory assumes that observed data come from a stationary process, where means and variances are constant over time. Graphs of economic time series, and the historical record of economic forecasting, reveal the invalidity of such an assumption. Consequently, we discuss the...

We describe the concept of cointegration, its implications in modelling and forecasting, and discuss inference procedures appropriate in integrated-cointegrated vector autoregressive processes (VARs). Particular attention is paid to the properties of VARs, to the modelling of deterministic...

We describe the concept of cointegration, its implications in modelling and forecasting, and discuss inference procedures appropriate in integrated-cointegrated vector autoregressive processes (VARs). Particular attention is paid to the properties of VARs, to the modelling of deterministic...

Using recently developed statistical tools for analyzing cointegrated I(2) data, this article models money, income, prices, and interest rates in Denmark. The final model describes the dynamic adjustment to short-run changes of the process, to deviations from long-run steady states, and to...

The paper discusses the dynamics of inflation and money growth in a stochastic framework, allowing for double unit roots in the nominal variables. It gives some examples of typical I(2) ’symptoms’ in empirical I(1) models and provides both a nontechnical and a technical discussion of the...

The economics profession appears to have been unaware of the long build-up to the current worldwide financial crisis and to have significantly underestimated its dimensions once it started to unfold. In our view, this lack of understanding is due to a misallocation of research efforts in...

The multivariate cointegration model in the autoregressive and the moving average form is discussed in terms of long run relations and common trends driving the system. The basic results needed for the cointegration analysis of processes integrated of order 2 are reviewed, and the notion of weak...

The persistent movements away from long-run benchmark values in real exchange rates, dubbed the PPP puzzle, observed in many real exchange rates during periods of currency float have been subject to much empirical research without resolving the puzzle. The paper demonstrates how the cointegrated...

The paper discusses methodological questions related to econometric time-series modelling of I(2) data. Long-run and medium-run relationships between two general price indices, the US CPI and WPI and four commodity prices indices, the WBI, CRBI, GSCI, and ECI are investigated in a multivariate...

Based on a money market analysis the paper discusses possible pitfalls in acroeconomic inference related to inadequate stochastic model formulation. A number of questions related to concepts such as empirical and theoretical steady-states, speed of adjustment, feed-back and interaction effects,...