7.3. Refer to formula (7.4) for the null variance of C — D. For large marginal totals, show that it equals approximately _2 v-EiPlw-EjPlj)"3

°C-D = g ·

(For Table 7.1, aC-D = 43, 941 compared to aC-D = 44,022 .) Show that the estimated null variance of (fic — Ð^) is approximately 4(1 ~ Ó,· P?+)d - Ó; P\j)

9n which equals 4/9n for Kendall's tau for fully ranked data.