The data come from all five week days and we also have information on whether or not a credit (or debit) card was used to pay the bill rather than cash. The frequency counts are shown in the two-way table in Table D.8. Find the chi-square statistic for this two-way table. Are the conditions met to use the chi-square distribution? Why or why not? Conduct the appropriate test to determine whether there is evidence of an association between the day of the week and whether the bill is paid in cash or with a credit/debit card.

Table D.8

In Data 2.12 on page 119, we introduce the dataset RestaurantTips containing information on the tipping patterns of patrons of the First Crush bistro in northern New York state. The data from 157 bills include 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. The first four variables are quantitative and the last three are categorical.

Data 2.12 on page 119

The owner of a bistro called First Crush in Potsdam, New York, is interested in studying the tipping patterns of its patrons. He collected restaurant bills over a two-week period that he believes provide a good sample of his customers. The data from 157 bills are stored in RestaurantTips and include 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.

Transcribed Image Text:

Wed Thurs Fri Total Mon Tues Cash 41 21 5 14 24 22 4 106 Card 12 51 Total 13 36 26 157 20 62