what is the difference b/w the xtreg and xtpcse routines

[Changho Moon]

I would like to analysis panel model with fixed effect and contemporaneous correlation.

So, I choosed the two belowed routines

xtpcse y x i.ind

xtgls y x i.ind, panels(correlated)

what is the difference b/w the xtreg and xtpcse routines?

[Maxence Morlet]

xtpcse creates particular standard errors relying on large T asympotitcs (you would need T/N to tend to infinity for xtpcse to yield valid standard errors, all else equal)

[Changho Moon]

thank you for your kindness and expertise!