In order to investigate factors that influence the size of tips given in restaurants, 107 waiters (Study 1) and 137 customers (Study 2) were asked various questions about tipping. The findings confirmed a number of hypotheses. Respondents said that they themselves tip more than most people. Waiters indicated that they were more generous tippers and were more accurate in their estimate of 15% of the bill than customers.
Tip size was reportedly increased by friendly service, good suggestions, excellent food, prompt delivery of the main course and check, a self-introduction by the waiter, and receiving separate checks. The tip was decreased by waiting a long time for a beverage and being seated in a bad location. Waiters identified more variables than did customers as being significantly associated with tip size, and they felt that excellent food, being in an expensive restaurant, and being seated in a bad location had greater effects on tipping than did customers.
When asked about characteristics of waiters who receive large or small tips, most waiters and customers mentioned the waiter's attitude and quality of service. There was much less consensus on the characteristics of high and low tippers. Gender was not significantly related to any responses. In general, although waiters and customers share many beliefs about tipping, waiters may be more aware than customers of the relevant characteristics of the situation and of the individuals involved.