XTREG error: weight must be constant within pidp
As I mentioned in a separate issue weeks ago, I am analysing life satisfaction and GHQ (using indresp files) from 18 waves of the BHPS plus 8 waves of the UKHLS for a total of 16 waves. I have been referring to indin91_lw as the longitudinal weight. My problem/issue is that I have told Stata that the data has a panel structure via xtreg pidp wave. I wish to run: xtreg y x1 x2 [pw=indin91_lw], fe but I keep getting the error, "weight must be constant within pidp". What is the easiest workaround that I can implement for this analysis?
Thanks so much!