st: calcuating unadjusted and adjusted means

["Fitzmaurice, Ann E." <a.e.fitzmaurice@abdn.ac.uk>]

Hi
I  run a regression and want to calculate the unadjusted and adjusted means of the sample included in the regression

I run the following where the variable bir_grp has four categories  was entered in the regression as i.bir_grp2 (sample_mod5 has previously been calculated)
Regress ............
predict xb
rename xb pred_m5
 mean pred_m5 if sample_mod5 ==1 , over (bir_grp2)

 adjust if sample_mod5==1, by (bir_grp2)

after this command I get an error message " variable miscbirth not found"

mean babywt2  if sample_mod5==1 ,over (bir_grp2)

This gives means  for the four groups which are identical between the two methods that work , but the confidence intervals are different,

Can  anyone advise how to calculate the group means before and after regression

Thanks

Ann

Ann E Fitzmaurice


The University of Aberdeen is a charity registered in Scotland, No SC013683.

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