Title: OA 6 Hypothesis Test
Course: PSYC 301 Statistical Methods in Psychol > Section: Second Part of Course

This is a very simple exercise for you to get your feet wet doing hypothesis tests. We will be doing hypothesis tests of increasing sophistication through the rest of the term. This is a simple test based on the concepts presented in Chapter 9 in the textbook, a test of proportions.

Imagine we have created a way to help people with migraine based on listening to light electronic music (such as that from State Azure) for 15 minutes.

A sample of 30 persons reporting to the Migraine Center (not a real place) where relaxation therapy is done. Traditional relaxation therapy is 50% effective (meaning 50% of the time headaches are relieved; this is not a real statistic but is an approximation from the literature on this topic).

We want to know if using light electronic music is more or less effective than the traditional relaxation techniques used in the Migraine Center (more or less than 50% effective).

Our scientific hypothesis is, therefore: Adding Light Electronic Music to Migraine Center Relaxation Techniques will eliminate more than 50% of migraine headaches. (Note, while our scientific hypothesis is stated for an increase in effectiveness [a one-tailed test], we would definitely pay attention to a decrease in effectiveness, therefore we will use a two-tailed [non-directional] test.)

Our mathematical hypotheses are, therefore:

\(H_{0}: \theta = 0.50\)

\(H_{1}: \theta \neq 0.50\)

Follow these steps to perform the hypothesis test in jamovi. Then, answer the questions below that.

1. Download this file from this link, then open it in jamovi: Migraine.omv
2. Notice you have two variables: Participant and Headache Relieved? Headache Relieved? has two levels, Y and N, which stand, respectively for Yes and No, indicating Yes, the headache was relieved or No, the headache was not relieved.
3. In the Analyses Tab, select Frequencies, then 2 Outcome Binomial.
4. Select Headaches Relieved? in the left hand box and click the arrow to move it to be analyzed.
5. Confirm that the Test value is 0.5, and change it to be 0.5 if it is a different value.
6. Confirm that the button next to ≠ Test value under Hypotheses is checked. If it is not selected change it to have that selected.
7. Then, write down the count of Yes and No responses, the proportion that are Yes responses and the p-value for the Yes responses.

You will see two p-values that are the same, one for Yes and one for No. That's because jamovi doesn't know which of those two you are particularly interested in talking about. They are the same because the probability of getting that count of Yes values out of 30 trials is completely the same mathematical question as the probability of getting that count of No values out of 30 trials.

Now write in the answer text box for this assignment responses to the following 4 items:

1. The count and proportion of Yes, Headache Relieved responses out of 30 participants
2. the probability of obtaining that outcome.
3. Indicate if you reject or retain the null hypothesis (H_0).
4. Describe in one sentence what was the probability information in the problem that lead you to your decision.

And, you're done!