Dear Community.   I am new in SAS and loosing my mind with this.   DATA TEST; INPUT ID UB CONS WGT; CARDS; 1 0 23 12 2 0 13 10 3 0 21 20 4 0 20 13 5 1 19 12 6 1 24 14 7 0 26 16 8 0 17 10 9 0 19 19 10 1 22 17 11 0 27 10 12 0 18 12 13 1 22 13 14 1 21 20 15 1 20 16 RUN;   Where: UB: is a dummy for whether one consumes a given beer or not CONS: is the reported number of bottle drank for a given period of time WGT is my sampling adjustment weight.   My data is from an online survey (no design), yet each respondent has a sampling adjustment weight to match the general population.   I want to estimate the mean consumption of beer and the corresponding 95% C.I for the two groups of UB (0,1) and test whether consumption is equal between the two groups.   Initially I ran this analysis in Stata and now I am tried to replicate it in SAS. I got the same weighted mean but different 95% C.I.   STATA Codes: Since STATA does not allow for weighted t-test, I ran a mean estimation (accounting for weight) and used test after mean estimation to compare the two means.   . mean CONS [pweight=WGT], over(UB) . test [CONS]0=[CONS]1   . test [CONS]0=[CONS]1 ( 1) [CONS]0 - [CONS]1 = 0   F( 1, 14) = 0.26 Prob > F = 0.6202     In SAS, I am getting the same means but different 95% Confidence intervals.   Analysis Variable : CONS UB N Obs Mean Lower 95% CL for Mean Upper 95% CL for Mean 0 9 20.6475410 17.5247509 23.7703311 1 6 21.3478261 19.6156577 23.0799944   Can some body help with this? ... View more