In: Statistics and Probability
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
statistically evident that the program is not working? Explain. (3
points)
Part B: Is it statistically evident from the
confidence interval that the program creates the discount with a
0.22 probability? Explain. (2 points)
Part C: Another random sample of receipts is
taken. This sample is five times the size of the original.
Seventeen 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? (2
points)
Part D: Using the margin of error from the second
sample in part C, is the program working as planned? Explain. (3
points)