A forensic psychologist conducted a study to examine whether being hypnotized during recall affects how well a witness can remember facts about an event. Nine participants watched a short film of a mock robbery, after which each participant was questioned about what he or she had seen. The five participants in the experimental group were questioned while they were hypnotized and gave 14, 18, 13, 20, and 10 accurate responses. The four participants in the control group gave 16, 20, 17, and 19 accurate responses. Using the .05 significance level, do hypnotized witnesses perform differently than witnesses who are not hypnotized?
a. Use the five steps of hypothesis testing.
b. Sketch the distributions involved.
c. Figure the effect size.
d. Explain the logic of what you did to a person who is familiar with the t test for a single sample, but who is unfamiliar with the t test for independent means. Be sure you explain how this problem differs from a t test for a single sample. Your answer should consist mainly of a thorough explanation of the characteristics of the comparison distribution and the logic of all the steps of figuring you did to determine those characteristics.
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