model {
    # Sequence read counts
    for (j in 1:J) {
        for (k in 1:K) {
            y[1:I, j, k] ~ dmulti(pi[1:I, j, k], N[j, k])
        }
    }

    # Cell probabilities for sequence reads
    for (j in 1:J) {
        for (k in 1:K) {
            for (i in 1:I) {
                pi[i, j, k] <- u[i, j, k] * r[i, j, k] / sum_ur[j, k]
