The article “Americans Say No to Electric Cars Despite Gas Prices” (USA TODAY, May 25, 2011) describes a survey of public opinion on issues related to rising gas prices. The survey was conducted by Gallup, a national polling organization. Each person in a representative sample of low-income adult Americans (annual income less than $30,000) and each person in an independently selected representative sample of high-income adult Americans (annual income greater than $75,000) was asked whether he or she would consider buying an electric car if gas prices continue to rise. In the low-income sample, 65% said that they would not buy an electric car no matter how high gas prices were to rise. In the highincome sample, 59% responded this way. The article did not give the sample sizes, but for the purposes of this exercise, suppose the sample sizes were both 300. One question of interest is whether the proportion who would never consider buying an electric car is different for the two income groups. Note that the sample sizes in the two groups—low-income adult Americans and high-income adult Americans—are large enough to satisfy the conditions for a large-sample test and a large-sample confidence interval for two population proportions. Even though the sample sizes are large enough, we can still use simulation based methods.

a. Based on these data, is it reasonable to conclude that the proportions of low-income and highincome adults who would never consider buying an electric car differ? Use large-sample methods to test the appropriate hypotheses using a significance level of 0.05.

b. Use the output at the top of the page to carry out a randomization test of the same hypotheses tested in Part (a).

c. Compare the conclusions in Parts (a) and (b). Would the same conclusion be reached in either case? Explain.