Question: The placebo effect. The placebo effect is particularly strong in patients with Parkinson's Disease. To understand the workings of the placebo effect, scientists measure activity at a key point in the brain when patients receive a placebo they think is an active drug and also when no treatment is given. The same six patients are measured both with and without the placebo, at different times.

a) Explain why the proper procedure to compare the mean response to placebo with control ( no treatment) is a matched pairs t test.

b) The six differences (treatment minus control) had \(\bar{D}=-0.326\) and s = 0.181. Is there significant evidence of a difference between treatment and control?

Describe the procedure you used in testing for significance.