lsat-test-model.txt

model {
# Rasch model
   for (j in 1:N) {
      for (k in 1:K) {
         logit(p[j,k]) <- beta*theta[j]-alpha[k];
         r[j,k] ~ dbern(p[j,k]);
      }
      theta[j] ~ dnorm(0,1);
   }
# Priors
   for (k in 1:K) {
      alpha[k] ~ dnorm(0,0.0001);
      a[k] <- alpha[k] - mean(alpha[]);
   }
   beta ~ dnorm(0,0.0001)I(0,);
}