摘要:In the standard forward-looking models of the recent literature, theoretical
optimal monetary policy rules imply much higher inertia of interest rates than
estimated historical policy rules. Motivated by the observation that theoretical
policy rules often assume perfect commitment on the part of the monetary
authority, this study formulates the monetary policy behavior with a continuum
from discretion to full commitment and, using this setup, seeks to match the
theory with evidence. It is shown that optimal instrument rules under imperfect
commitment exhibit less inertia on the policy instrument; the degree of inertia
declines as the policy moves from full commitment to discretion. Therefore,
under the assumption that the monetary authorities operate somewhere in between
discretion and commitment, historically observed policy behavior can be
reconciled with the optimal policy rules—even in a purely forward-looking
framework. As a by-product, we propose a method to measure the stance of
monetary policy from the perspective of discretion versus commitment. To test
our proposal, we estimate a structural monetary policy rule for the Federal
Reserve, which nests discretion and commitment as special cases. Empirical
results suggest that recent practice of monetary policy has been closer to
commitment than the policy pursued in the 1970s