The following information was obtained from two independent samples selected from two normally distributed populations with unknown but equal standard deviations. Do the data present suf?cient evidence to indicate that there is a difference in the mean for the two populations?
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Sample 1:
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15
|
13
|
11
|
14
|
10
|
12
|
7
|
12
|
11
|
14
|
15
|
|
|
Sample 2:
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18
|
16
|
13
|
21
|
16
|
19
|
15
|
18
|
19
|
20
|
21
|
14
|
(a) Use the ANOVA approach to test the appropriate hypotheses. Use α = 0.01.
(b) Test the appropriate hypothesis by using the two-sample t-test for comparing population means. Compare the value of the t-statistic to the value of the F -statistic calculated in part (a).