/*  Use GLIMMIX in SAS to fit a 
    Poisson regression model with
	random suject effects to
    the epileptic seizure data
    rom Thall and Vail(1990).  */

/*  This program is stored in the file

                 seizglmm.sas        */


options linesize=64;

data set1;
  infile 'c:\stat565\seizures.dat';
  input y1-y4 trt base age;
        patient = _N_;
  age=(age-29);
  y0 = base/4;
  z = 1;
run;

proc format; value trt 0 = 'Placebo'
                       1 = 'Progabide';

proc print data=set1; run;


/*  Modify the data file to put 
    repeated measures on different lines.
    Also create a time variable. */

data set2; set set1;
  y = y0; time=0; xt=time; output;
  y = y1; time=2; xt=time; output;
  y = y2; time=4; xt=time; output;
  y = y3; time=6; xt=time; output;
  y = y4; time=8; xt=time; output;
  run;


/*  Fit a model use GLIMMIX to include
    a random patient effect  */

%inc  'c:\stat565\glmm800.sas' /
            nosource;
  run;

/*  Log-linear models with fixed and
    random effects */

%glimmix(data=set2,
   stmts=%str(
     class patient;
     model y = trt time time*time age age*trt /
           solution;
     random intercept / type=un subject=patient;),
	 error=poisson, link=log, 
     converge=1e-8, maxit=20, out=setp
     )
run;


proc print data=setp (obs=5); run;