Essays on Dynamic Effects of Exchange Rate Volatility Shocks on a Small Open Economy

Motivated by the existence of time-varying volatility in exchange rates, the paper investigates the effects of exchange rate volatility shocks on a small open economy. First, we use a high-frequency dataset to generate a volatility measure for the period, instead of the traditional moving average standard deviation of exchange rates. The structural VAR impulse responses utilizing the volatility measure yield more significant and robust reactions of real variables to a volatility shock. Consumption, ouput, investment and net export exhibit non-trivial decrease upon impact of the shock. On the contrary, an exchange rate level shock and the traditional volatility measure fail to generate robust impulse responses under different Cholseky orderings.;Second, we develop a theoretical model based on a standard New Keynesian small open economy, which can replicate the effects of a volatility shock observed in the VAR result. We solve the model up to a third order approximation so that the solution includes an explicit time-varying volatility term. The model impulse responses exhibit that real variables respond to a volatility shock and they are qualitatively consistent with the VAR result. The underlying mechanism is precautionary saving. The result is sensitive to various parameters such as the openness parameter and the elasticity of inter-temporal substitution.;Finally, we make a welfare analysis regarding the optimal monetary policy. Two types of welfare measures are used: the unconditional mean of utility and the conditional welfare. The conditional welfare suggests that policy makers should raise the interest rate when volatility increases. The seemingly counter-intuitive result is due to the fact that the conditional welfare measure reflects dynamic response of the agent throughout her life-cycle. Under the optimal policy suggested by the conditional welfare, the initial consumption adjustment is severe but agents work less and eventually enjoy a higher level of consumption from savings carried over from earlier periods.