Monetary Policy in a Low Interest Rate World
研究了当名义利率长期偏低时，央行传统政策规则会导致经济表现恶化，而风险调整和承诺策略能改善通胀和产出，对央行制定政策有参考价值。
Nominal interest rates may remain substantially below the averages of the last half century, because central banks' inflation objectives lie below the average level of inflation, and estimates of the real interest rate that are likely to prevail over the long run fall notably short of the average real interest rate experienced during this period. Persistently low nominal interest rates may lead to more frequent and costly episodes at the effective lower bound (ELB) on nominal interest rates. We revisit the frequency and potential costs of such episodes in a world of low interest rates, using both a dynamic stochastic general equilibrium (DSGE) model and the Federal Reserve's largescale econometric model, the FRB/US model. Four main conclusions emerge. First, monetary policy strategies based on traditional, simple policy rules lead to poor economic performance when the equilibrium interest rate is low, with economic activity and inflation more volatile and systematically falling short of desirable levels. Moreover, the frequency and length of ELB episodes under such policy approaches are estimated to be significantly higher than in previous studies. Second, a risk adjustment to a simple rule-whereby monetary policymakers are more accommodative, on average, than prescribed by the rule-ensures that inflation averages its 2 percent objective, and requires that policymakers systematically seek inflation near 3 percent when the ELB is not binding. Third, commitment strategies, whereby monetary accommodation is not removed until either inflation or economic activity overshoots its longrun objective, are very effective in both the DSGE and FRB/US models.