Question

• The following are mood scores for 12 participants before and after watching a funny video clip (higher values indicate better mood). Before After Before After 7 2 4 2 5 4 7 3 5 3 4 1 7 5 4 1 6 5 5 3 7 4 4 3 a. Calculate the paired-samples t statistic for these mood scores. b. Using a one-tailed hypothesis test that the video clip improves mood, and a p level of 0.05, identify the critical tvalues and make a decision regarding the null hypothesis. c. Using a two-tailed hypothesis test with a p level of 0.05, identify the critical t values and make a decision regarding the null hypothesis. I need to show all steps. Also can you send me the answer only and not post it on the web. I am paying Chegg to get help and the answer to my question is posted and then everyone turns in my exact answer regarding the manner it is answered and I get in trouble.

Answer 1

Let d = before -after

Following table shows the calculations:

Before	After	d=before-After	(d-mean)^2
7	2	5	6.671889
5	4	1	2.007889
5	3	2	0.173889
7	5	2	0.173889
6	5	1	2.007889
7	4	3	0.339889
4	2	2	0.173889
7	3	4	2.505889
4	1	3	0.339889
4	1	3	0.339889
5	3	2	0.173889
4	3	1	2.007889
Total	36	29	16.916668

Sample size: n=12

Now,

Two tailed test:

One tailed test: If the video clip improves mood then difference should be negative. So,

(a) The test statistics is

t = 6.752

(b)

The critical value is 1.796

Since test statistics lies in the rejection region so we reject the null hypothesis. That is we cannot conclude that the video clip improves mood.

(c)

The critical values are -2.201 and 2.201

Since test statistics lies in the rejection region so we reject the null hypothesis.