Assume that the two samples are independent simple random samples selected from normally distributed populations. do not assume that the population standard deviations are equal. refer to the accompanying data set. use a 0.01 significance level to test the claim that the sample of home voltages and the sample of generator voltages are from populations with the same mean. if there is a statistically significant? difference, does that difference have practical? significance?
day home (volts) generator (volts)
1 123.9 124.9
2 123.7 124.6
3 123.9 125.2
4 123.3 124.9
5 123.3 124.9
6 123.9 124.4
7 123.9 124.7
8 124.0 124.4
9 123.2 124.8
10 123.6 124.4
11 123.3 124.3
12 123.9 125.4
13 123.8 124.8
14 123.9 124.1
15 123.7 124.3
16 123.3 124.2
17 124.0 124.6
18 123.8 124.0
19 123.0 124.2
20 123.2 124.4
21 123.0 124.1
22 123.6 124.2
23 123.8 124.5
24 123.2 124.1
25 123.2 124.7
26 123.0 124.4
27 123.7 124.2
28 123.3 124.6
29 123.9 124.6
30 123.0 124.7
31 123.2 124.2
32 123.1 124.2
33 123.7 124.4
34 123.3 124.5
35 123.8 124.4
36 124.0 124.4
37 123.8 124.9
38 123.3 124.4
39 123.3 124.5
40 123.4 124.6
(a) calculate the test statistic
t=
(b) find p-vlaue
p-value=
(c) make a conclusion about the null hypothesis and a final conclusion that addresses the original claim.
(reject/no reject) h0. there (is/is not) sufficient evidence to warrant rejection of the claim that the sample of home voltages and the sample of generator voltages are from populations with the same mean. the difference (is/is not) statistically significant.
(e)if there is a statistically significant? difference, does that difference have practical? significance?
a. the sample means suggest that the difference does not have practical significance. the generator could be used as a substitute when needed.
b. the sample means suggest that the difference does have practical significance. the generator could not be used as a substitute when needed.
c. the sample means suggest that the difference does have practical significance. the generator could not be used as a substitute when needed.
d. the difference is not statistically significant.