Imagine you are a researcher who believes that a relaxation technique involving visualization will help people with mild insomnia fall asleep faster. You randomly select a sample of 20 participants from a population of mild insomnia patients and randomly assign 10 to receive visualization therapy. The other 10 participants receive no treatment.
You then measure how long (in minutes) it takes participants to fall asleep. Your data are below. The numbers represent the number of minutes each participant took to fall asleep.
|
No Treatment (X1)
|
Treatment (X2)
|
|
22
|
19
|
|
18
|
17
|
|
27
|
24
|
|
20
|
21
|
|
23
|
27
|
|
26
|
21
|
|
27
|
23
|
|
22
|
18
|
|
24
|
19
|
|
22
|
