Question 4 (10 parts):

A large car dealership recently sent out a satisfaction survey to randomly selected new car

customers. The survey included several statements about satisfaction, and customers

responded using the 5-point agreement scale below:

1 = Strongly Disagree; 2 = Disagree; 3 = Neither Agree nor Disagree; 4 = Agree; 5 = Strongly Agree

Two of the statements on the survey were:

1. I am satisfied with the sales associate who sold me my new vehicle.

2. I am satisfied with the finance manager who helped me finance my new vehicle.

Data from a random sample of 75 customers who bought and financed new vehicles at the

dealership are in the Midterm Exam Workbook. Using the data, answer the following questions.

questions.

a. Set up the appropriate hypothesis test to determine whether customers were more

satisfied with their sales associate than with the finance manager. Specifically, state

the null hypothesis and the alternative hypothesis. Are the data paired or unpaired?

b. Compute the test statistic and the associated p-value for the hypothesis test in

(b)?

c. Based on the results in (c), what is your conclusion about whether customers

were more satisfied with their sales associate than with the finance manager at

α = .05?

d. Now use the responses for the two statements in the data to compute the sample

proportions (̂’s) of customers who agreed those statements (i.e., responded with a 4

or a 5), indicating that they were satisfied with (i) their sales associate or (ii) the

finance manager. Report these two sample proportions (̂’s).

e. Compute 95% confidence intervals for the true mean proportion, , of customers who

were satisfied with (i) their sales associate or (ii) the finance manager.

f. Set up the appropriate hypothesis test to determine whether the proportion of

customers who were satisfied with their sales associate is greater than the proportion

who were satisfied with the finance manager. Specifically, state the null hypothesis

and the alternative hypothesis. Is this a one-tailed test to the left, a one-tailed test to the right, or a two-tailed test?