Dear Irrational (an experiment with toilet paper)

July 24, 2008 BY danariely

One of the positive side effects of writing Predictably Irrational is that sometimes people try their own versions of these experiments. Here is one email describing an experiment on cheating and toilet paper – demonstrating the wide range of application of behavioral economics….

Dear Professor Ariely,

I am a fan of your research. I particularly liked your experiments on cheating (i.e. the non-existent “MIT honor code” and 10 Commandments example) and thought that I could apply your hypothesis in an experiment of my own.

I live in a house near the U.C. Berkeley campus (where I just graduated last semester). The house is shared with many housemates, and most of us do not know each other before moving in. Moreover, this summer a bunch of foreign exchange students are also living in the house. This living arrangement has led to a number of problems– namely the stealing of toilet paper. We have a cleaning guy that comes once a week to clean our bathrooms and restock our toilet paper. On Sunday, he puts out 3 fresh rolls of toilet paper for each toilet in the house. However by Monday evening, all the toilet paper would be gone. It is clear that certain housemates are hoarding the tissue paper for private use.

Since I do not look forward to missing toilet paper when I need to use the restroom, I tried to think of ways to stop the hoarding. I did not want to confront anyone directly because my goal was not to point fingers, but to get back the TP! So what I did was to follow your experiments: I simply put a note in the bathroom asking that housemates would not take the toilet paper for personal use outside the restroom.

I put the note up in one of the upstairs bathrooms on Tuesday afternoon after discovering that there was no more toilet paper in any of the bathrooms (there are 3 in total). A couple hours later (!), one fresh roll of toilet paper magically appeared in the bathroom where I placed the note. It worked! And I also checked downstairs where I did not leave a note– no rolls of TP there. And two days later, another fresh roll of toilet paper appeared in the upstairs bathroom.

Toilet paper “magically reappearing” has *never* happened all summer– when its gone, its usually gone for good. So I was quite pleased that my note had worked in putting an end to the hoarding/stealing. And so thank you for the inspiration! Behavioral economics is certainly applicable to daily life!