To the 544 trick-or-treaters who walked up to Joshua Tasoff's porch in Monrovia, Calif., it was just a stormy Halloween night replete with costumes and candy.
To Tasoff, it was the perfect setting for a science experiment.
A behavioral economist at Claremont Graduate University, Tasoff was curious about the ways in which costumes might affect someone's identity and their ethical choices. He thought he might be able to see it in action by testing whether the costumes children wore had any influence on their propensity to cheat in a simple game.
"You have all these kids that are getting dressed up in costumes once on a year," Tasoff said. "I thought, 'This is a golden opportunity -- I have to do something.'"
Clothes make the man, as they say, and there's evidence that they influence behavior as well. For instance, researchers have found that lab coats can make the wearer perform better on attention-related tasks, and that school uniforms seem to reduce disciplinary referrals.
If lab coats and uniforms could make a difference, what about a full-blown costume?
Costumes have coincided with anomalous behavior since Halloween's earliest days, Tasoff said. The holiday is derived from Samhain, a Celtic spiritual festival in which pranksters donned costumes to hide their identities.
Tasoff wasn't the first behavioral economist to turn All Hallow's Eve into a scientific project. Dean Karlan at Northwestern University has engaged trick-or-treaters to study their tolerance of ambiguity, the influence of Michelle Obama on their healthy eating choices, and various other questions. Dan Ariely of Duke University has enlisted candy-seekers to learn about the ways that free goods affect kids' decision making.
Tasoff and his graduate students came up with a two-part plan to test whether costumes connected to the trick-or-treaters' propensity to cheat. Going in, they suspected that kids wearing "good guy" costumes would be more honest than those wearing the "bad guy" outfits.
One part involved asking trick-or-treaters about their costumes: Who are you today? Is that a "good guy" or a "bad guy"? Do you do good things or evil things? (Children were also asked how old they were, and a researcher wrote down other relevant information, including their genders and whether parents accompanied them.)