27. Pain. Researchers comparing the effectiveness of

Chapter 22, Problem 27

(choose chapter or problem)

27. Pain. Researchers comparing the effectiveness of twopain medications randomly selected a group of patients who had been complaining of a certain kind of joint pain.They randomly divided these people into two groups,then administered the pain killers. Of the 112 people inthe group who received medication A, 84 said this painreliever was effective. Of the 108 people in the othergroup, 66 reported that pain reliever B was effective.a) Write a 95% confidence interval for the percent ofpeople who may get relief from this kind of joint painby using medication A. Interpret your interval.b) Write a 95% confidence interval for the percent ofpeople who may get relief by using medication B.Interpret your interval.c) Do the intervals for A and B overlap? What do youthink this means about the comparative effectivenessof these medications?d) Find a 95% confidence interval for the difference inthe proportions of people who may find these medicationseffective. Interpret your interval.e) Does this interval contain zero? What does that mean?f ) Why do the results in parts c and e seem contradictory?If we want to compare the effectiveness of these twopain relievers, which is the correct approach? Why?