Investigating the Effectiveness of Government Expenditures and Taxes During Business Cycles: Application of Threshold Vector Auto-regression Model

Fiscal multiplier is one of the most important factors which governments and economic policymakers rely on to conduct fiscal policy. This multiplier, which shows the effectiveness of fiscal policy in stimulating domestic production and economic stabilization, has always been a contentious issue among economists and researchers, because there is no theoretical agreement on the size of this coefficient. Therefore, several researchers have tried to empirically estimate the Fiscal multiplier. This effort, which has doubled after the global crisis of 2007-2008 due to the significant role of this policy tool in reducing crises, is the main purpose of this study. This paper estimates the instantaneous and cumulative Fiscal multiplier using quarterly data of Iran economy during 1990 to 2017, using a non-linear threshold auto-regressive model. The results of TAR test and TVECM test showed that the integration of some variables used in the research is nonlinear. Similarly, the Co-integration relationship between the variables is nonlinear. Also estimation of TVAR model and simulated nonlinear impact response functions showed that the multiplier of government expenditures during the recession is greater than the boom period. This is opposite for tax. Also the largest multiplier among the three fiscal policy instruments related to current government expenditures.