/****************************************************************/ /* S A S S A M P L E L I B R A R Y */ /* */ /* NAME: MIXEX2 */ /* TITLE: Documentation Example 2 for PROC MIXED */ /* Repeated Measures */ /* PRODUCT: STAT */ /* SYSTEM: ALL */ /* KEYS: Mixed Linear Models */ /* PROCS: MIXED */ /* DATA: */ /* */ /* SUPPORT: Tianlin Wang */ /* REF: */ /* MISC: */ /* */ /****************************************************************/ *---------------Repeated Measures Example-----------* | Data represent a repeated measures example where | | an unstructured variance matrix is fit. Data are | | from Pothoff and Roy (1964) and are analyzed by | | Jennrich and Schluchter (1986). | *---------------------------------------------------*; data pr; input Person Gender $ y1 y2 y3 y4; y=y1; Age=8; output; y=y2; Age=10; output; y=y3; Age=12; output; y=y4; Age=14; output; drop y1-y4; datalines; 1 F 21.0 20.0 21.5 23.0 2 F 21.0 21.5 24.0 25.5 3 F 20.5 24.0 24.5 26.0 4 F 23.5 24.5 25.0 26.5 5 F 21.5 23.0 22.5 23.5 6 F 20.0 21.0 21.0 22.5 7 F 21.5 22.5 23.0 25.0 8 F 23.0 23.0 23.5 24.0 9 F 20.0 21.0 22.0 21.5 10 F 16.5 19.0 19.0 19.5 11 F 24.5 25.0 28.0 28.0 12 M 26.0 25.0 29.0 31.0 13 M 21.5 22.5 23.0 26.5 14 M 23.0 22.5 24.0 27.5 15 M 25.5 27.5 26.5 27.0 16 M 20.0 23.5 22.5 26.0 17 M 24.5 25.5 27.0 28.5 18 M 22.0 22.0 24.5 26.5 19 M 24.0 21.5 24.5 25.5 20 M 23.0 20.5 31.0 26.0 21 M 27.5 28.0 31.0 31.5 22 M 23.0 23.0 23.5 25.0 23 M 21.5 23.5 24.0 28.0 24 M 17.0 24.5 26.0 29.5 25 M 22.5 25.5 25.5 26.0 26 M 23.0 24.5 26.0 30.0 27 M 22.0 21.5 23.5 25.0 ; proc mixed data=pr method=ml covtest; class Person Gender; model y = Gender Age Gender*Age / s; repeated / type=un subject=Person r; run; /* first-order autoregressive */ proc mixed data=pr method=ml; class Person Gender; model y = Gender Age Gender*Age / s; repeated / type=ar(1) sub=Person r; run; /* random coefficients model */ proc mixed data=pr method=ml; class Person Gender; model y = Gender Age Gender*Age / s; random intercept Age / type=un sub=Person g; run; proc mixed data=pr method=ml covtest; class Person Gender; model y = Gender Age Gender*Age / s; repeated / type=cs subject=Person r; run; /* compound symmetry specified on RANDOM statement */ proc mixed data=pr method=ml; class Person Gender; model y = Gender Age Gender*Age / s; random Person; run; proc mixed data=pr method=ml; class Person Gender; model y = Gender Age Gender*Age / s; repeated / type=cs subject=Person group=Gender; run;