Monetary Policy Does Matter: Control Causality and Superexogeneity.

In this paper, the sufficiency of superexogeneity for control causality is exploited in the case of monetary policy and real output. The superexogeneity of the formulation of monetary policy for the real output gap is tested and found to be true implying a causal link from monetary policy to the real output gap. Given the empirical evidence, the Lucas Critique appears to be a theoretical possibility but not empirically relevant in this case. Copyright 2002 by Blackwell Publishing Ltd