Analysis of Nonlinear Behavior of the Central Bank's Monetary Policy in Uncertainty Conditions: Smooth Transition Regression Model (STR)

The purpose of this study is to analyze the nonlinear behavior of monetary policy at the Central Bank of the Islamic Republic of Iran in uncertainty condition. To achieve this goal, the nonlinear behavior of the central bank's reaction function to the inflation uncertainty in the form of smooth Transition Regression model (STR) is estimated using seasonal data during the 1997:1-2015:3 periods. The results of this study indicate that the variable behavior and regime change in monetary policy of the central bank of Iran in the various conditions of inflation. By passing the uncertainty of inflation from a threshold level, the behavior of monetary policy has been changed so that the coefficients of the model are consistent with the Taylor rule. Based on the results of the present study, it is suggested to consider the economic uncertainty index in order to determine the optimal monetary policy.