var
   theta[2], X[J], Z[J], mu[J], p[J], y[J], n[J], alpha, beta, tau, sigma2,
   theta0;
model {
   theta[1] ~ dnorm(0.0,1.0E-3);  
   theta[2] ~ dnorm(0.0,1.0E-3);
   tau <- 1/sigma2;		
   for (j in 1:J) {
      mu[j]       <- alpha + beta*Z[j];
      X[j]         ~ dnorm(mu[j],tau);
      logit(p[j]) <- theta[1] + theta[2] * (X[j] - mean(X));
      y[j]         ~ dbin(p[j],n[j]);
   }
   theta0    <- theta[1] - theta[2]*mean(X);
}