Question: Refer to Exercise. Of the 193 placebo takers, 43 reported headaches.
a. Compute a 95% confidence interval for the true population proportion that would get headaches after taking a placebo.
b. Notice that a higher proportion of placebo takers than Seldane-D takers reported headaches. Use that information to explain why it is important to have a group taking placebos when studying the potential side effects of medications.
Exercise: An advertisement for Seldane-D, a drug prescribed for seasonal allergic rhinitis, reported results of a double-blind study in which 374 patients took Seldane-D and 193 took a placebo (Time, 27 March 1995, p. 18). Headaches were reported as a side effect by 65 of those taking Seldane-D.
a. What is the sample proportion of Seldane-D takers who reported headaches?
b. What is the standard deviation for the proportion computed in part a?
c. Construct a 95% confidence interval for the population proportion based on the information from parts a and b.
d. Interpret the confidence interval from part c by writing a few sentences explaining what it means.