What would the formula for a 95% prediction interval for an ARMA(2,2) model be?
The specific model I am using is: an ARIMA(2,0,2) with non-zero mean, with the following parameter estimates:
Coefficients:
ar1 ar2 ma1 ma2 mean
1.3421 -0.6738 -0.2027 -0.2564 1544.4039
s.e. 0.0984 0.0801 0.1261 0.1097 131.9242
sigma^2 estimated as 761965: log likelihood=-932.08
AIC=1876.17 AICc=1876.95 BIC=1892.58