A small open economy modelling: A Bayesian DSGE approach

Abstract

Examining the business cycle and the monetary transmission mechanism in a small open economy based on the macroeconomic models is vital for successfully implementing forward-looking and counter-cyclical macroeconomic policies. In the context, this thesis focuses on the importance of various modelling implications (i.e., frictions and shocks) in developing empirically viable small open economy dynamic stochastic general equilibrium (DSGE) models. The thesis comprises three self-contained chapters on formulating, estimating and evaluating the DSGE models using Bayesian methods and data for Australia and the United States (US) (or G7 for Chapter 2), as well as a general thesis introduction and conclusion.

Chapter 2 investigates the quantitative role of a cost channel of monetary policy and an uncovered interest rate parity (UIP) modification in an estimated small open economy DSGE model. For this purpose, a small open economy New Keynesian DSGE model developed by Justiniano and Preston (2010a) (i.e., benchmark model for the thesis) is augmented to incorporate the cost channel and the UIP modification based on a forward premium puzzle. The empirical analysis shows that introducing the cost channel and the UIP modification into the estimated model improves its ability to fit business cycle properties of key macroeconomic variables and to account for the empirical evidence on the monetary transmission mechanism.

Chapter 3 assesses the importance of news shocks in a small open economy DSGE model for analysing business cycle properties of macroeconomic aggregates, including labour market variables. To this end, the model in Chapter 2 is enlarged in Chapter 3 to include (i) the theory of invoulntary unemployment proposed by Galí (2011), (ii) an endogenous preference shifter, similar to that used by Galí et al. (2011), and (iii) both news (anticipated) and unanticipated components in each structural shock. The results show that the estimated model is able to qualitatively replicate the existing VAR-based results (e.g., Kosaka 2013, Kamber et al. 2014 and Theodoridis and Zanetti 2014) on news driven business cycles, and the presence of news shocks has the potential to improve the model fit. Another important finding is that news shocks have been the main drivers of the Australian business cycle in the inflation-targeting period.

Chapter 4 examines the significance of financial frictions and shocks in a small open economy DSGE model for explaining macroeconomic fluctuations. In doing so, Chapter 4 has further extended the model in Chapter 3 to a rich DSGE model in the two-country setting with involuntary unemployment, financial frictions and shocks. The main results include (i) the presence of financial accelerator improves the model fit, (ii) the financial accelerator amplifies and propagates the effects of monetary policy shocks on output, but dampens the effects of technology and labour supply shocks in Australia and the US, and (iii) financial shocks (i.e., shocks to the credit spread) are important for explaining investment and output fluctuations in both countries.

Finally, this thesis provides implications for designing macroeconomic policies and building empirically viable open economy DSGE models to analyse the transmission mechanism of monetary policy and the business cycle.