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5. The Green's function G, of an ARMA(n.m) model is given by: G = 0.4(0.9) 121 Assume x, = 0 and a, 's are: T 0 1 2 3 a, 0 0.5 -1 1 Compute x, by using the Green's function. (b) Find the corresponding ARMA model and its parameters Check (a) by using the difference equation form of the model 4 5 -2 2 5. The Green's function G, of an ARMA(n.m) model is given by: G = 0.4(0.9) 121 Assume x, = 0 and a, 's are: T 0 1 2 3 a, 0 0.5 -1 1 Compute x, by using the Green's function. (b) Find the corresponding ARMA model and its parameters Check (a) by using the difference equation form of the model 4 5 -2 2