model melanoma;

 const
  N = 255,   # number of subjects
# r = 1,      # if exponential model is used
  p = 4;    # number of covariates

 var
 t[N],      # failure time for each subject
 t.cen[N],  # censoring time for each subject
  mu[N], r,  # Weibull parameters 
#mu[N],     # if exponential model is used
 beta[p], beta0,   # regression coefficients
 trt[N],     # treatment covariate
  breslow[N], # breslow thickness covariate
  age[N],     # age covariate
  sex[N],     # sex covariate
  eta[N];     # the linear predictor x'beta


 data t, t.cen, trt, breslow, age, sex in "e1684w.dat";
 inits in "e1684w.in";

 {
 for(i in 1:N) {                           # t.cen[i] = 0

     t[i]  ~ dweib(r,mu[i]) I(t.cen[i],);  # if subject i fails
     
#    eta[i] <- beta0 + beta[1]*trt[i]+beta[2]*breslow[i]+beta[3]*age[i]+beta[4]*sex[i];
     eta[i] <- beta0 + beta[1]*trt[i]; 
     mu[i] <- exp(eta[i]);   

     }

    for(j in 1:p) {
       beta[j] ~ dnorm(0,.0001);   # prior
       }

     beta0 ~ dnorm(0,.0001);
     r ~ dgamma(1.0,.0001);
     
}