Question

A.)You wish to test the following claim (HaHa) at a significance level of α=0.001α=0.001.  dd denotes the mean of the difference between pre-test and post-test scores.       

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:

post-test	pre-test
58	73.9
71.3	53.3
65.2	74.5
57.2	48.4
66.1	39.6
49.6	35.9
60.8	103.6
70.8	96.9
49.2	13.2
65.5	72.2
51.2	42.4
45.9	66.4
55.3	32
59.5	54.9
64.7	85.2
64.1	39.2
78.8	63.7
50.8	29.1
69.2	65.3
56.7	49.3
63.1	102.3
54.8	64.9

• Make sure to choose the appropriate column for Sample 1 and 2 so that you are estimating the improved post-test score: μ2−μ1μ2-μ1

1. What is the test statistic for this sample?
   
   test statistic =  Round to 3 decimal places.
   
2. What is the p-value for this sample? Round to 4 decimal places.
   
   p-value =

B.)A survey of 48 people was conducted to compare their self-reported height to their actual height. The difference between reported height and actual height was calculated.

You're testing the claim that the mean difference is greater than 1.5.

From the sample, the mean difference was 1.85, with a standard deviation of 0.66.

Calculate the test statistic, rounded to two decimal places

  

C.)

Your marketing department believes it has a new commercial that will increase the percent of people who plan on purchasing from one of your stores in the next month. You take a sample of people and before you show them the new commercial, ask them if they are planning on purchasing from one of your stores in the next month. You then show them the new commercial and follow up by asking again if they plan on purchasing from one of your stores in the next month. In your data analysis, you look at the difference of (post-commercial)-(pre-commercial). You want to test the claim that there is no difference between the pre and post commercial mean percentages, and do so at the α=0.10α=0.10 level.

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-commercial	post-commercial
28.4	83.8
41.9	10.2
34.4	-56.3
39.7	6
43.2	-4.4
41	-13.9
34.1	-65.9
43.9	-21.1
45.4	42.7
40.8	-37.9
30.6	-9.3
38.2	-18
44.2	-55.8
41.5	96.9
41.1	-12.5
38.7	74.4

1. What is the test statistic for this sample?
   
   test statistic =  Round to 4 decimal places.
   
2. What is the p-value for this sample? Round to 4 decimal places.
   
   p-value =

Answer 1