Question 2: A. Using a sample of size 1,000 from a stationary time series, the following estimates of autocovariance and partial autocorrelation functions were computed: [10] Lag ACF 0 1 2 3 4 5 6 7 0.596 PACF 1 -0.276 -0.463 -0.325 -0.058 -0.024 0.011 0.027 -0.008 -0.044 -0.028 -0.045 -0.122 B. Based on the above estimates, choose between the model classes AR(p) and MA(q) for this data, and suggest a suitable model order p or q. Justify your answers. Can you estimate the model parameters For the following two time series plot and corresponding ACF and PACF plots below, determine the orders p and q of a tentative ARMA( p, q) model that can be used for this data [10] 10- 08- 06- 04- 02- 0.0- -08- -0.8- -10- 90 106 120 136 160 25 30 36 Timme 02. -08- -1.0- 90 106 120 135 150 Time 6 C. Determine whether the following AR processes are stationary [10] Z₁ = 20 +0.752.1+ a ze 50+0.2z-1-0.42-2+ at 2-10+0.3z-1+0.5z+-2+ a 02- 1.0- 0.8- Lag 25 30 35