Hello everyone,
I am a newbie in using Stata, so hope you guys will explain everything clearly and in plain language.
I have read a lot of previous posts before but I'm so confused because almost posts with a similar subject were about fe model.
My database has N = 24 and T=12 => 288 observations. I'll present the steps of running my model as below:
1. Running OLS with command of -reg depvar indepvar-.
2. Running Correlation matrix and VIF to check multicollinearity.
3. Running fe model (-xtreg depvar indepvar, fe) and re model (-xtreg depvar indepvar, re)
4. Conducting the Breusch and Pagan Lagrangian multiplier test (-xttest0-) and Hausman test (-hausman-) to select the appropriate model, which is REM method.
5. Performing 3 tests for RE model as Pesaran's test of cross- sectional independence (-xtcsd, pesaran abs-), Breusch and Pagan Lagrangian multiplier test for heteroskedasticity (-xttest0-)
Wooldridge test for autocorrelation (-xtserial depvar indepvar-). The results show my RE model has heteroskedasticity and autocorrelation.

I have some questions:
1. Is my modeling process good enough?
2. Could I use command of -xtreg depvar indepvar, re robust/vce(cluster)/cluster(N) (N stand for the numbers of firms) in order to fix heteroskedasticity and autocorrelation like FE model? And then I will use these RE robust results for my finale conclusions?
3. Or I should run -xtreg depvar indepvar, re robust- and -xtreg depvar indepvar, fe robust-, then choose appropriate model by robust hausman with command of -xtoverid-? I also don't know how to use -xtoverid- command.

Thank you so so much for your help. I've been stuck with all these thoughts for months.
Best regards,
Linh Bui