Quality Progress, February 2005, reports on the results achieved by Bank of America in improving customer satisfaction and customer loyalty by listening to the voice of the customer. A key measure of customer satisfaction is the response on a scale from 1 to10 to the question:
Considering all the business you do with Bank of America, what is your overall satisfaction with Bank of America? Suppose that a random sample of 350 current customers results in 195 customers with a response of 9 or 10 representing customer delight.
Find a 95 percent confidence interval for the true proportion of all current Bank of America customers who would respond with a 9 or 10. Are we 95 percent confident that this proportion exceeds .48, the historical proportion of customer delight for Bank of America?© BrainMass Inc. brainmass.com December 15, 2022, 8:20 pm ad1c9bdddf
a) Given the sample size n = 350, the number of customers responded 9 or 10 X = 195. Hence the sample proportion (See attached) = 0.5571
95% confidence interval for the true ...
The solution determines the confidence interval for customer satisfaction and testing.