PROC MIXED output   Nested data analysis in proc mixed      I want to set up a nested 3-level model in proc mixed, say repeated observations within 'CS_No_stud' within 'pt_num_school' within g'roup_district'. I do something like:   proc mixed data=data noclprint covtest noitprint PLOTS(MAXPOINTS=NONE); class pt_num_school group_district CS_No_stud; model strut_neointimal_thickness= /solution ddfm=bw ; random int/ sub=group_district; random int/ sub=pt_num_school(group_district); repeated / sub=CS_No_stud(pt_num_school *group_district) type=cs; run;   then, the result is in attach file... why group_district does not estimate?? please let me know~~~~ASAP THANK YOU~~ ... View more