Question

This dataset contains data recorded from 157 restaurant bills at a bistro in NY over a two week period and is considered to be representative of all bills at this particular restaurant. The dataset includes the amount of the bill, size of the tip, percentage tip, number of customers in the group, whether or not a credit card was used, day of the week, and a coded identity of the server.   

Describe how you could use a confidence interval to analyze a portion a dataset in a way that would help the owner of the restaurant better understand his customers. Be sure to use proper statistical terminology. You do not have to actually calculate the confidence interval

Please help!!!

Answer 1

There are two groups in this case which are independent of each other.

Group 1: Customers who used a credit card to pay

Group 2: Customers who did not use a credit card to pay

The null hypothesis, Ho: There is no difference in the percentage tips between the two groups

You may calculate the confidence interval in the following way to test the above null hypothesis:

Let's calculate the 95% confidence interval for the difference in the percentage tips. The independent samples t-test formula can be used here. Tt could be gauged that which customers are more generous, who pay by credit card or cash. If the confidence interval contains 0, there is no significant difference in the tips. In this way, the restaurant owner can understand its customers.