19. A research study has demonstrated that self-hypnosis can be an effective treatment for allergies (Langewitz, Izakovic, & Wyler, 2005). The researchers recruited a sample of patients with moderate to severe allergic reactions. The patients were trained to focus their minds on a specific place, such as a ski slope in winter, where allergies did not bother them. The participants were then tested for allergic reactions to pollen under two circumstances: once without using self-hypnosis and once after using self-hypnosis. This sample of n 16 averaged MD 21 points lower when they were using self-hypnosis with SS 1215 for the difference scores. Use the data to estimate how much effect self-hypnosis would have on the general population of individuals with moderate to severe allergies. Make a point estimate and an 80%

confidence interval estimate.