Question

In: Statistics and Probability

A program was created to randomly choose customers at a shoe store to receive a discount....

A program was created to randomly choose customers at a shoe store to receive a discount. The program claims 15% of the receipts will get a discount in the long run. The manager of the shoe store is skeptical and believes the program's calculations are incorrect. She selects a random sample and finds that 12% received the discount. The confidence interval is 0.12 ± 0.05 with all conditions for inference met.

Part A: Using the given confidence interval, is it statistically evident that the program is not working? Explain.

Part B: Is it statistically evident from the confidence interval that the program creates the discount with a 0.15 probability? Explain.

Part C: Another random sample of receipts is taken. This sample is six times the size of the original. Twelve percent of the receipts in the second sample received the discount. What is the value of margin of error based on the second sample with the same confidence level as the original interval?

Part D: Using the margin of error from the second sample in part C, is the program working as planned? Explain.

Solutions

Expert Solution


Related Solutions

A program was created to randomly choose customers at a clothing store to receive a discount....
A program was created to randomly choose customers at a clothing store to receive a discount. The program claims 22% of the receipts will get a discount in the long run. The owner of the clothing store is skeptical and believes the program's calculations are incorrect. He selects a random sample and finds that 17% received the discount. The confidence interval is 0.17 ± 0.05 with all conditions for inference met. Part A: Using the given confidence interval, is it...
A program was created to randomly choose customers at a clothing store to receive a discount....
A program was created to randomly choose customers at a clothing store to receive a discount. The program claims 22% of the receipts will get a discount in the long run. The owner of the clothing store is skeptical and believes the program's calculations are incorrect. He selects a random sample and finds that 17% received the discount. The confidence interval is 0.17 ± 0.05 with all conditions for inference met. Part A: Using the given confidence interval, is it...
Suppose the manager of a shoe store wants to determine the current percentage of customers who...
Suppose the manager of a shoe store wants to determine the current percentage of customers who are males. How many customers should the manager survey in order to be 99% confident that the estimated (sample) proportion is within 10 percentage points of the true population proportion of customers who are males? z0.10 z0.05 z0.04 z0.025 z0.01 z0.005 1.282 1.645 1.751 1.960 2.326 2.576
Suppose the manager of a shoe store wants to determine the current percentage of customers who...
Suppose the manager of a shoe store wants to determine the current percentage of customers who are males. How many customers should the manager survey in order to be 92% confident that the estimated (sample) proportion is within 10 percentage points of the true population proportion of customers who are males? z0.10 z0.05 z0.04 z0.025 z0.01 z0.005 1.282 1.645 1.751 1.960 2.326 2.576
A store surveys customers to see if they are satisfied with the service they receive. Samples...
A store surveys customers to see if they are satisfied with the service they receive. Samples of 75 surveys are taken. One in six people are unsatisfied. What is the variance of the mean of the sampling distribution of sample proportions for the number of unsatisfied customers? What is the variance for satisfied customers?
A certain store gives its customers a discount on the goods they buy based on a...
A certain store gives its customers a discount on the goods they buy based on a peculiar manner. The discount percentage is equal to each customer's remainder of weight to age, weight % age. The maximum discount percentage allowed is 10. If the remainder is greater than 10, the discount percentage is recomputed as the remainder of 10. For example, a customer whose weight is 175 lbs and age 61, buys an item costing $60.97. The discount percentage = 175...
At two different branches of a department store, pollsters randomly sampled 100 customers at store 1...
At two different branches of a department store, pollsters randomly sampled 100 customers at store 1 and 80 customers at store 2, all on the same day. At store 1, the average amount purchased was $41.25 per customer with a sample standard deviation of $24.25. At store 2 the average amount purchased was $45.75 with a sample standard deviation of $34.76. a) Construct a 95% confidence interval for the mean amount purchased per customer in Store 1 and Store 2....
At two different branches of a department store, pollsters randomly sampled 100 customers at store 1...
At two different branches of a department store, pollsters randomly sampled 100 customers at store 1 and 80 customers at store 2, all on the same day. At store 1, the average amount purchased was $41.25 per customer with a sample standard deviation of $24.25. At store 2 the average amount purchased was $45.75 with a sample standard deviation of $34.76. a) Construct a 95% confidence interval for the mean amount purchased per customer in Store 1 and Store 2....
The Schmedley Discount Department Store has approximately 300 customers shopping in its store between 9 A.M....
The Schmedley Discount Department Store has approximately 300 customers shopping in its store between 9 A.M. and 5 P.M. on Saturdays. In deciding how many cash registers to keep open each Saturday, Schmedley’s manager considers two factors: customer waiting time (and the associated waiting cost) and the service costs of employing additional checkout clerks. Checkout clerks are paid an average of $8 per hour. When only one is on duty, the waiting time per customer is about 10 minutes (or...
QUESTION 19 Jean guesses that 35% of customers at a local grocery store will choose the...
QUESTION 19 Jean guesses that 35% of customers at a local grocery store will choose the self check-out lane over the full service cashier lane. Throughout one day, she gathers data by observing 228 customers in the store. She finds that 74 of them choose the self check-out lane. Was her guess reasonable? Assume 95% confidence. (Hint: You may use either a confidence interval or hypothesis test to help you answer this question.) A. Yes, her guess was reasonable. B....
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT