13.1 Use the results of Theorem 7.3.8 to evaluate the efficacy of the twosample Wilcoxon rank-sum test statistic of (8.2.1) for the location model FY(x) ¼ FX(x  u) where

(a) FX is N(mX, s2) or FX(x) ¼ F½(x  mX)=s

(b) FX is uniform, with FX(x) ¼

0 x  1=2 x þ 1=2 1=2 < x  1=2 1 x > 1=2 8<

:

(c) FX is double exponential, with FX(x) ¼

1 2

 

elx x  0 1 

1 2

 

elx x > 0