8  For a more detailed discussion of this sort of issue in forecasting using models, see Sims (2002) and Hendry and Clements (2003).
4  BIS Review 46/2004  Learning To this we can add that learning is crucial, which is to say that observing the pattern of forecast errors and seeking to draw conclusions for our ‘model’ of the economy and therefore its future behaviour can, hopefully, improve future forecasts.