Macroeconomic uncertainty and macroeconomic performance: are they related?

We use a very general multivariate GARCH-M model and G7 monthly data covering the 1957-2003 period to test for the impact of real and nominal macroeconomic uncertainty on inflation and output growth.Our evidence supports a number of important conclusions. First, in most countries output growth uncertainty is a positive determinant of the output growth rate. Second, there is mixed evidence regarding the effect of inflation uncertainty on inflation and output growth. Hence,uncertainty about the inflation rate is not necessarily detrimental to economic growth. Finally, there is mixed evidence on the effect of output uncertainty on inflation.