Question

You wish to test the following claim (HaHa) at a significance level of α=0.005α=0.005. For the context of this problem, μd=PostTest−PreTestμd=PostTest-PreTest one data set represents a pre-test and the other data set represents a post-test. Each row represents the pre and post test scores for an individual.

      Ho:μd=0Ho:μd=0
      Ha:μd≠0Ha:μd≠0

You believe the population of difference scores is normally distributed, but you do not know the standard deviation. You obtain the following sample of data:

pre-test	post-test
63.4	104.2
65.8	90
18.2	17.8
55.2	54.8
70	34.6
33.1	41.3
24	29.6
49.5	37.4
59.3	96.3
61.5	86.9
54.7	48.5
64.2	34.9
64.9	-7
52.4	71.1
75.8	77.1
54.3	26.1
59.8	118.5
39.7	40.2
59.8	107.7
41.2	8.4

What is the test statistic for this sample?
test statistic =  (Report answer accurate to 4 decimal places.)

What is the p-value for this sample?
p-value =  (Report answer accurate to 4 decimal places.)

The p-value is...

• less than (or equal to) αα
• greater than αα

This test statistic leads to a decision to...

• reject the null
• accept the null
• fail to reject the null

As such, the final conclusion is that...

• There is sufficient evidence to warrant rejection of the claim that the mean difference of post-test from pre-test is not equal to 0.
• There is not sufficient evidence to warrant rejection of the claim that the mean difference of post-test from pre-test is not equal to 0.
• The sample data support the claim that the mean difference of post-test from pre-test is not equal to 0.
• There is not sufficient sample evidence to support the claim that the mean difference of post-test from pre-test is not equal to 0.

Answer 1

Test statistic t = 0.3587

p-value = 0.7238

The p-value is greater than α

This test statistic leads to a decision to fail to reject the null

As such, the final conclusion is that:

There is sufficient evidence to warrant rejection of the claim that the mean difference of post-test from pre-test is not equal to 0.