Question: Susceptibility to hypnosis. The Computer-Assisted Hypnosis Scale (CAHS) is designed to measure a person's susceptibility to hypnosis. In computerassisted hypnosis, the computer serves as a facilitator of hypnosis by using digitized speech processing coupled with interactive involvement with the hypnotic subject. CAHS scores range from 0 (no susceptibility) to 12 (extremely high susceptibility). A study in Psychological Assessment (March 1995) reported a mean CAHS score of 4.59 and a standard deviation of 2.95 for University of Tennessee undergraduates. Assume that μ = 4.29 and σ = 2.95 for this population. Suppose a psychologist uses CAHS to test a random sample of 50 subjects.
(a) Would you expect to observe a sample mean CAHS score of y¯ = 6 or higher? Explain.
(b) Suppose the psychologist actually observes y¯ = 6.2. Based on your answer to part a, make an inference about the population from which the sample was selected.