Optimal Monetary Policy and Estimating the Credibility of Monetary Policy in Iran using the DSGE Approach

To achieve the optimal monetary policy, attention must be paid to a key element: the credibility of monetary policy authorities. Credibility plays a crucial role in the effectiveness of these policies, as it facilitates the attainment of targeted variables with minimal fluctuation and social cost. Conversely, in times of unexpected economic shocks, discretionary policy becomes optimal, providing policymakers with flexibility to make appropriate monetary decisions. Conversely, in times of unexpected economic shocks, the use of discretionary policy is optimal because it provids policy makers with more flexibility to make appropriate monetary decisions. In this study, we pursued two goals. First, we constructed a Dynamic Stochastic General Equilibrium (DSGE) model for an open and small economy according to the conditions of Iran's economy. We then estimated the of credibility of Iran’s monetary policy authority in managing both the inflation rate and exchange rate yielding figures of0.1019 and 0.0099 respectively. Then, in order to find the optimal discretionary monetary policy under the influence of two scenarios of low and high credibility of the monetary policy authorities, we utilized the minimum loss function approach. The results of the model indicated that the credibility of the monetary policy maker in Iran is very low in both the inflation rate and the exchange rate. Examining the loss function of the central bank showed that, in both scenarios, minimizing the exchange rate gap while assigning equal weight to other objectives leads to the lowest possible loss function value.