Based on the information given for each of the following studies, decide whether to reject the null hypothesis. For each, give (a) the Z-score cutoff (or cutoffs) on the comparison distribution at which the null hypothesis should be rejected, (b) the Z score on the comparison distribution for the sample score, and (c) your conclusion. Assume that all populations are normally distributed.
(I) Population
Study Sample Score p Tails of Test
A 5 1 7 .05 1 (high predicted)
B 5 1 7 .05 2
C 5 1 7 .01 1 (high predicted)
D 5 1 7 .01 2
(II) Population
Study Sample Score p Tails of Test
A 100.0 10.0 80 .05 1 (low predicted)
B 100.0 20.0 80 .01 2
C 74.3 11.8 80 .01 2
D 16.9 1.2 80 .05 1 (low predicted)
E 88.1 12.7 80 .05 2