OPTIONS LS = 75;

DATA a;

  INFILE 'cabg.dat';
  
  INPUT AnnVol_L AnnVol_U Patients Deaths  Pct_exp ;
  
  AnnVol = (AnnVol_L + AnnVol_U)/2;
  
  Expected = (Pct_exp/100)*Patients;
  
  Vol_pts = AnnVol * Patients;
  
  LogE_Y = Log(Pct_exp/100) + Log(Patients);
  
  Inv_Vol = 1/AnnVol;
  
PROC PRINT;
  
PROC GENMOD;

  MODEL Deaths = AnnVol / dist   = Poisson
                          link   = log
                          offset = LogE_Y ;
						  
PROC GENMOD;

  MODEL Deaths = AnnVol / dist   = Poisson
                          link   = identity
                          offset = Expected ;
                          
PROC GENMOD;

  MODEL Deaths = Inv_Vol / dist   = Poisson
                          link   = identity
                          offset = Expected ;
                          
                          RUN;