A study if the impact of stress on the amount of beta-endorphins released in the blood was reported. Researchers took beta-endorphin levels for 19 patients 12 hours before surgery and again 10 minutes before surgery. If you assume that time before surgery (12 hrs vs. 10 minutes) is a manipulation of stress, does the data indicate that stress affects beta-endorphin levels in the blood? Use a two tailed hypothesis alpha =.05. The data are below.
Insert the mean and SD for the 12 hour and 10 minute condition below
Subject 12 hours 10 minutes
1 10 6.5
2 6.5 14.0
3 8.0 13.5
4 12.0 18.0
5 5.0 14.5
6 11.5 9.0
7 5.0 18.0
8 3.5 42.0
9 7.5 7.5
10 5.8 6.0
11 4.7 25.0
12 8.0 12.0
13 7.0 52.0
14 17.0 20.0
15 8.8 16.0
16 17.0 15.0
17 15.0 11.5
18 4.4 2.5
19 2.0 2.0
(1)State the null hypothesis:
(1)State the nondirectional alternative hypothesis:
Insert the appropriate values below
∑D= ∑D2= SSdif=
SSdiff=
(2) t=
(1) critical t=