# How to treat arima models with some non-statistical significant p-values?

This is a pretty simple question but didn't find anything relevant here, so hope it's not a duplicate.

I've used statsmodels python library to find the best parameters (minimizing the AIC) for an ARIMA model and the result of the fitting with such parameters set [(1,1,1)x(1,1,0,12)] on the data is:

Now, while that model will minimize the AIC value, I see some coefficients with p-values that indicate non statistical significance (ar1 with 0.966 and ar.S with 0.543). What does that mean? Should I set those coefficients to 0 or the corresponding parameters and refit the model?

Any hint or clarification is greatly appreciated.

Thank you

• 2) Yes, you can. 1) I means that your library couldn't work with incomplete polynoms and fit all $\phi / \theta$ values of characteristic polynomials. May 7 '19 at 16:00
• sorry Dmitriy, could you elaborate more on that? Also, would you suggest alternative libraries? Thanks May 7 '19 at 17:38
• Unfortunately, I can recommend only R libraries. So, I think your library should support fixed values for $\phi / \theta$ parameters. May 7 '19 at 17:41