When I worked in a restaurant during my college years, I noticed a trend among many of my customers; I would often get tipped more if I wrote something on their receipt at the end of the meal. For customers where I wrote “Thank You!” or something to that effect on the receipt, I would often end up with nearly double the amount of tips I would get if I merely gave them the check. Once I noticed this, I decided to test this theory.
I decided to alternate between writing and not writing on a customer’s receipt for my next thirty tables, until I got a sample of fifteen for each one. After I reached thirty, I calculated the amount of tips I got based on percentage of check – I measured this instead of a dollar total because each table had a differently priced meal, and I did not want that to affect my results. Once I was done, I noticed a nearly 30% increase in tips from tables where I made the extra effort to write on their check.
My research methods were similar to those psychologists use in that I measured a trend in how an environment change affected the behavior of the subject. I wanted to see if leaving a more personal mark on their receipt (the last impression a customer gets of a waiter) would create a more favorable impression, and thus become more tip-worthy. If I were to do it again, I would likely get a bigger sample size to gain a more statistically significant result. Also, I would experiment with seeing how effective different sayings would be – I just wrote “Thank You!” on each check the first time, but I could have sample sets where the variables would include writing my name under that, or other sayings like “Thanks for Coming!” This would determine whether it’s the content of the note that is significant, or merely the fact that the waiter put forth extra effort.