# Chapter 25 SAS Code for the Repeated Measures

```
/* Compound Structure */
proc mixed;
class program subj time;
model strength = program time program * time;
random subj(program) ;
run;
/* alternative code for compound structure */
proc mixed;
class program subj time;
model strength program time program * time;
repeated time / subject = subj type = cs; /* cs */
run;
/* AR(1) */
proc mixed;
class program subj time;
model strength program time program * time;
repeated time / subject = subj type = ar(1);
run;
/* General Positive Definite Structure */
proc mixed;
class program subj time;
model strength program time program * time;
repeated time / subject = subj type = un;
run;
```

AIC and BIC for repeated measures in SAS:

- \(AIC = -2\ell(\hat\theta) + 2k\)
- \(BIC = -2\ell(\hat\theta) + k\ln(n)\)
- k = number of variance parameters
- n = total number of independent subjects