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Assume the following covariance stationary ARMA(2, 2):
Which of the following statements about this ARMA(2,2) model is correct?
A
The model is stationary because the AR coefficients sum to less than 1
B
The model is invertible because the MA coefficients sum to less than 1
C
The unconditional mean of the process is 0.2
D
The model violates the stationarity condition
E
The long-run variance of the process is infinite
F
The model is both stationary and invertible