In: Statistics and Probability
In an article in the Journal of Advertising, Weinberger and Spotts compare the use of humor in television ads in the United States and in the United Kingdom. Suppose that independent random samples of television ads are taken in the two countries. A random sample of 450 television ads in the United Kingdom reveals that 137 of them use humor, while a random sample of 520 television ads in the United States reveals that 175 of them use humor.
(a) Calculate the point estimate of the difference between the proportion of U.K. ads using humor and the proportion of U.S. ads using humor.
(b) What kind of confidence interval is appropriate for this problem?
(c) Calculate a 96 percent confidence interval for the difference between the proportion of U.K. ads using humor and the proportion of U.S. ads using humor.
(d) Interpret the interval.
(e) Can we be 96 percent confident that there is a difference between the proportion of U.K. ads using humor and the proportion of U.S. ads using humor? Explain