Vector autoregressive models are widely used in empirical macroeconomics. Unfortunately, they are subject to the curse of dimensionality. Single-equation general-to-specific reduction procedures using PcGets are proposed to overcome the problem: Starting from the unrestricted VAR, standard testing procedures eliminate statistically-insignificant variables in every equation of the VAR, with diagnostic tests checking the validity of reductions. Weak exogeneity conditions are derived for the efficiency of such single-equation reduction procedures. In Monte Carlo experiments the proposed reduction strategy recovers the DGP from a large unrestricted VAR with size and power close to commencing from the DGP itself. The application to a US monetary system illustrates its feasibility for the analysis of large macroeconomic data sets.
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