Interest Rate in the Objective Function of the Central Bank and Monetary Policy Design

We analyze two well-known specifications of the interest rate term in the central bank's objective function, and find that the inflation response to a positive demand shock is positive (intuitive) under one specification and negative (counter-intuitive) under the other. We show that the difference between the two responses can be mitigated by a Taylor-type rule and depends on the interest rate inertia. A super-inertial interest rate, which is more aggressive and leads to the counter-intuitive response, may be helpful in an environment of low inflation due to negative demand shocks, such as the current global economic environment.