# Question

Citibank, which has a major credit card division, has designed a promotion that the firm hopes will encourage its customers to increase their current credit card usage. To test the effectiveness of the promotion, Citibank monitored the monthly balances of 25 customers who were informed of the promotion and the monthly balances of 25 customers who were not aware of it. Assume the population variance for the credit card balances are equal. The results can be found in the Excel file Citibank 2. xlsx.

a. Using α = 0.05, perform a hypothesis test to determine if the average credit card balance is higher for customers aware of the promotion than it was for customers unaware of the promotion.

b. Construct a 90% confidence interval to estimate the average difference in credit card balance before and after the promotion.

c. Verify your results using PHStat.

d. Identify the p value and interpret the result.

e. What assumptions need to be made in order to perform this procedure?

a. Using α = 0.05, perform a hypothesis test to determine if the average credit card balance is higher for customers aware of the promotion than it was for customers unaware of the promotion.

b. Construct a 90% confidence interval to estimate the average difference in credit card balance before and after the promotion.

c. Verify your results using PHStat.

d. Identify the p value and interpret the result.

e. What assumptions need to be made in order to perform this procedure?

## Answer to relevant Questions

The Excel file golf scores. xlsx contains a random sample of golf scores from two highly competitive sons of a certain statistics author. Each son claims he is the better golfer. Assume the population variances for each ...Consider the following partially completed one- way ANOVA summary table: a. Complete the remaining entries in the table. b. How many population means are being tested? c. Using α = 0.05, what conclusions can be made ...Consider the following data collected for a randomized block ANOVA: a. Calculate the total sum of squares (SST). b. Partition the total sum of squares (SST) into its three components. c. Using α = 0.05, what conclusions ...The superintendent of the Red Clay School District is concerned about the sick time taken by teachers and administrators. More specifically, she would like to know if there is a difference in the number of hours of sick time ...Consider the following partially completed two way ANOVA summary table: a. Complete the remaining entries in the table. b. How many replications are present for each cell? c. Using α = 0.05, is there significant ...Post your question

0