7.8. In testing Ho: independence for an r x r table, suppose that «,,· = 1 for all i and tiij — 0 for all ( ö j .

(a) Show that an exact test that uses the Pearson X2 to order all tables having the given margins has P-value = 1.0.

(b) Explain why a two-sided test using an ordinal criterion such as C — D or a correlation to order all the tables with the given margins has Pvalue

= 2/r!.