options ps=54 ls=76 nodate nonumber; FILENAME website HTTP "http://www.stat.ufl.edu/~winner/data/breath_reg.dat" data one; infile website; input subject brtime male bac subjmean bac_c; brtime_c=brtime-5.5; run; proc mixed; class subject; model bac = brtime / solution; random intercept / sub=subject type=un solution; run; proc mixed; class subject; model bac = brtime / solution; random intercept brtime / sub=subject type=un solution; run; proc mixed; class subject; model bac = brtime male brtime*male / solution; random intercept brtime / sub=subject type=un solution; run;