Threshold Impact of Combined Fiscal Decentralization on Economic Growth in Provinces of Iran: Panel Smooth Transition Regression Approach

The relationship between financial decentralization and economic growth has been one of the crucial issues in economics in recent decades. Financial decentralization could affect economic growth and consequently development programs and the expansion of regional balance policies. This study investigates the nonlinear behavior of economic growth and financial decentralization in the Iranian provinces during the period 2004-2016 using a panel smooth transition regression model as one of the prominent models of regime change. A hybrid financial decentralization index is extracted using the principal component analysis technique and it is used as a transfer variable to study the changes in economic growth in the nonlinear model. Results of estimation confirm a nonlinear relationship between the variables under study and propose a dual-regime model with a threshold of 3.1941 and a slope parameter of 4.2869. So, the effect of combined financial decentralization on growth of the provinces is asymmetric. Thus, with increasing decentralization in the first regime, economic growth becomes positive and after crossing the threshold and entering the second regime, it becomes negative due to the costs associated with increasing financial decentralization. Therefore, the relationship between hybrid financial decentralization and the economic growth of the provinces can be shown as an inverse parabola.