=+12.18. Consider a special case of Example 12.11 with ni = k, 1 ≤ i ≤ m, where k ≥ 2. Show that in this case, the estimating equation of Jiang (1998a), which is (12.52) with B = diag(1, 1

m), is equivalent to the optimal estimating equation—that is, (12.52) with B = B∗ given by (12.53).