A researcher was interested in the effects of caffeine on sleep. She measured how many minutes...

A researcher was interested in the effects of caffeine on sleep. She measured how many minutes it took for ten participants to fall asleep. Half of the participants drank a liter of caffeinated soda before going to sleep while the other half were only allowed to drink water. Summary data of minutes are presented below. Did the caffeine increase the length of time it took to fall asleep (a =.05)?

Water Group Caffeine Group

18 22

15 15

19 20

14 21

14 19

a. Name the test to be conducted and why you selected it:

b. State the null and alternative hypotheses:

c. State the CV and the decision rule. Sketch the rejection region:

d. In addition, calculate the value of eta2 (h2).

e. Write out an APA style conclusion based on this finding:

Solutions

Expert Solution

Let denote the average time to take fall asleep for water group and caffeine group respectively.

Conclusion : There is enough evidence to support the claim that the caffeine significantly increase the length of time it took to fall asleep

milcah answered 2 hours ago

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