Question 1 (10 marks) (a) A researcher estimated an MA (1) -GARCH(1,1) model for the daily percentage returns on the ASX 200 Australian stock market index over the last five weeks of trading and obtained the results: re = 0.34 + 1.05ut-1 + ue o = 0.27 +0.050-1 +0.9302-1 The log-likelihood was 718.2 (0) (ii) Is the process for reinvertible in this model? Justify your answer. (0.5 marks) Is the conditional variance of r, always positive in this model? Justify your answer. (0.5 marks) Will a large shock to returns in this model lead to forecasts of the conditional variance that are high and remain high for many periods into the future? Justify your answer. (2 marks) (iii)