dear, i estimate the same model firstly by using proc surveyreg and secondly by using proc glimmix. i want robust standard errors (as i work with longitudinal data with repeated observations of individuals "mergeid" .  i get the same estimates in surveyreg and in glimmix, but i get however different pvalues. how do you explain that?   this is the command in proc surveyreg: proc surveyreg data=l (where=(gender=2)); model retired = age56 age57 age58 age59 age60 age61 age62 age63 age64 age65 eli1 eli2 eli3 age56*eli1 age57*eli1 age58*eli1 age59*eli1 age60*eli1 age61*eli1 age62*eli1 age62*eli1 age63*eli1 age64*eli1 age65*eli1 age56*eli2 age57*eli2 age58*eli2 age59*eli2 age60*eli2 age61*eli2 age62*eli2 age62*eli2 age63*eli2 age64*eli2 age65*eli2 age56*eli3 age57*eli3 age58*eli3 age59*eli3 age60*eli3 age61*eli3 age62*eli3 age62*eli3 age63*eli3 age64*eli3 age65*eli3 lang edu2 edu3 edu4 health1 health2 health4 health5 married divorce ch001_ maxassim u laggdprate gdprate; cluster mergeid; run;   this is the command in proc glimmix: proc glimmix data=l(where=(gender=2 )); class mergeid; model retired = age56 age57 age58 age59 age60 age61 age62 age63 age64 age65 eli1 eli2 eli3 age56*eli1 age57*eli1 age58*eli1 age59*eli1 age60*eli1 age61*eli1 age62*eli1 age62*eli1 age63*eli1 age64*eli1 age65*eli1 age56*eli2 age57*eli2 age58*eli2 age59*eli2 age60*eli2 age61*eli2 age62*eli2 age62*eli2 age63*eli2 age64*eli2 age65*eli2 age56*eli3 age57*eli3 age58*eli3 age59*eli3 age60*eli3 age61*eli3 age62*eli3 age62*eli3 age63*eli3 age64*eli3 age65*eli3 lang edu2 edu3 edu4 health1 health2 health4 health5 married divorce ch001_ maxassim u laggdprate gdprate/solution; random residual /subject=mergeid ; run;   thanks for helping me!   ... View more