한국과 미국의 통화정책 탈동조화에 따른 국내 통화정책의 비선형성 효과 분석

This study empirically examines the nonlinear effects of Korea's domestic monetary policy depending on whether its direction is synchronized with that of the United States. Given Korea's characteristics as a small open economy, the effectiveness of domestic monetary policy can vary according to the degree of synchronization with U.S. monetary policy, which exerts a significant influence on global financial conditions. Utilizing a two-stage estimation method based on the Taylor-type rule framework, this study identifies monetary policy shocks and analyzes their effects on output under synchronized and desynchronized periods. The empirical results indicate that during desynchronized periods, the impact of domestic monetary policy on output is significantly weaker compared to synchronized periods, confirming the existence of nonlinear effects. Moreover, by analyzing the indirect transmission channel through which monetary policy shocks affect the current account via the exchange rate reveals that, during the period of desynchronizing, the exchange rate's impact on the current account became more direct and significant, offsetting the effects of global demand fluctuations on the current account. Furthermore, the subsample analysis suggests that the gap in monetary policy effectiveness between synchronization and desynchronization has narrowed after the COVID-19 pandemic, implying a strengthening of Korea’s monetary policy autonomy. These findings highlight the necessity for small open economies to carefully consider both global financial conditions and domestic economic factors when formulating monetary policy, especially under conditions of policy desynchronization.