Brand loyalty in the automotive industry can be measured by the percentage of brand owners who purchase again. Suppose Cars.com would like to investigate if there is a difference in brand loyalty between Chevrolet and Buick owners.

A random sample of 160 Chevrolet owners found that 68 had previously owned a Chevrolet. A random sample of 150 Buick owners found that 76 had previously owned a Buick.

a. Using a = 0.05, perform this hypothesis test for Cars.com.

b. Construct a 95% confidence interval to estimate the difference in the proportion of owners who purchased the same brand of car for these two populations. Interpret your result.

c. Determine the p-value and interpret the results.

d. Verify your results using PHStat.

AppendixLO1