Dear community,

I am deciding among Pooled OLS, Fixed and Random Effects panel models in the presence of first-order autocorrelation ( null hypothesis of Wooldridge test for autocorrelation in panel data is not rejected) . Thus, i have found out that the command . xtregar gives reliable estimates in the presence of AR1. So I run the FE and RE tests ( e.g., . xtregar, re) and then the default Hausman test . hausman fixed random. The null hypothesis is rejected, meaning FE is to be chosen.

1) Am i doing everything correctly till now?

An now i want also to exclude Pooled OLS by running the Breusch and Pagan Lagrangian multiplier test for random effects. Usually it is done with the comand of . xttest0 but it returns an error message last estimates not found r(301)

2) Which command/ procedure would be appropriate in order to exclude Pooled OLS?
I want to mention that there is no heteroscedasticity problem, only the autocorrelation is the issue.

Thank you a lot for support!

Kind Regards
Farid