model {
         # Likelihood
            for (i in 1 : Nareas) {
               for (k in 1 : Ndiseases) {
                  Y[i, k] ~ dpois(mu[i, k])
         # Note dimension of S is reversed:
                  log(mu[i, k]) <- log(E[i, k]) + alpha[k] + S[k, i]
         # rows=k, cols=i because mv.car assumes rows represent variables
         # (diseases) and columns represent observations (areas).
               }
         # The GeoBUGS map tool can only map vectors, so need to create separate vector
         # of quantities to be mapped, rather than an array (i.e. RR[i,k] won't work!)
         # area specific relative risk for disease 1 (oral)
               RR1[i] <- exp(alpha[1] + S[1, i])
         # area specific relative risk for disease 2 (lung)   
               RR2[i] <- exp(alpha[2] + S[2, i])
            }

         # MV CAR prior for the spatial random effects
         
# MVCAR prior
            S[1:Ndiseases, 1 : Nareas] ~ mv.car(adj[], weights[], num[], omega[ , ])
            for (i in 1:sumNumNeigh) {
               weights[i] <- 1
            }

          # Other priors
             for (k in 1 : Ndiseases) {
                alpha[k] ~ dflat()
             }
         
# Precision matrix of MVCAR
            omega[1 : Ndiseases, 1 : Ndiseases] ~ dwish(R[ , ], Ndiseases)
         # Covariance matrix of MVCAR   
            sigma2[1 : Ndiseases, 1 : Ndiseases] <- inverse(omega[ , ])
         # conditional SD of S[1, ] (oral cancer)
            sigma[1] <- sqrt(sigma2[1, 1])
         # conditional SD of S[2,] (lung cancer)
         sigma[2] <- sqrt(sigma2[2, 2])
         # within-area conditional correlation
            corr <- sigma2[1, 2] / (sigma[1] * sigma[2])
         # between oral and lung cancers.
         
    mean1 <- mean(S[1,])
            mean2 <- mean(S[2,])

         }