A time-varying covariate in a panel date regression

[John Andrews]

Dear all,

I have a panel where all variables are indexed it apart from one covariate, say Der, that is indexed t.

How can I run this model in Stata?

I have this sample of code (using fixed effects or random effects)

clear
xtset Id Time
sort Id Time
xtreg y x Der, fe
xtreg y x Der, re

Is that correct?

Thanks

[George Ford]

Normally you'd have a fixed effect for time, which will eat the Der variable.

use reghdfe to absorb multiple fixed effects.