Two groups of guinea pigs were injected, respectively, with 0.5 and 1.0 milligrams of a tranquilizer, and the following are the numbers of seconds it took them to fall asleep:
0.5 mg dose: 8.2 10.0 10.2 13.7 14.0
1.0 mg dose: 9.7 13.1 11.0 7.5 13.3
Use Wilcoxon rank-sum test to test at the .10 level of significance to test the claim that the difference in dosage have significant effect on the length of time it takes guinea pigs to fall asleep.
(a) Set up hypotheses. : :
(b) Find the observed value. Utilize the table below if you like.
(c) State the rejection region.
(d) State your conclusion and the reason.
(e) Interpret the conclusion in part (d).