One waiter recorded information about each tip he received over a period of a few months working in one restaurant. He collected several variables:
tip in dollars,
bill in dollars,
sex of the bill payer,
whether there were smokers in the party,
day of the week,
time of day,
size of the party.
In all he recorded 244 tips. The data was reported in a collection of case studies for business statistics (Bryant & Smith 1995).
A data frame with 244 rows and 7 variables
Bryant, P. G. and Smith, M (1995) Practical Data Analysis: Case Studies in Business Statistics. Homewood, IL: Richard D. Irwin Publishing: