Behavioural versus Experimental Economics: Evidence from the bedroom

People often ask me why I didn’t become a professional chess player.  Basically the answer is because I’m not good enough, but I usually prefer to save face and instead tell them about that other passion that has taken over my career path, behavioural economics.  I usually get the inevitable “What’s that?” question, but sometimes (albeit more rarely) I get a response something like, “Behavioural economics… it’s something like economics in labs, right?”

Not quite, but it’s a common mistake.  Many people these days confuse behavioural and experimental economics, and they do overlap a little.  Basically, both fields look to move outside classical economics and draw a closer focus on what actually happens in the real world.  But while experimental economics uses laboratory experiments and surveys to figure out real-world behaviour, behavioural economics takes psychological research and tries to re-theorise it into economic terms.

Sounds pretty much the same, you might think (or, alternatively, it might have all sounded like gobbledy-gook).  But it’s not.  As a behavioural economist, I might take a phenomenon that is easily observable in real life (for instance, that people are not totally selfish and stop to help injured strangers, even if there’s no reward) and chuck it back into an economic theory.  An experimental economist, on the other hand, would have a little more difficulty testing this hypothesis. 

But surely they could just survey people, right?  I hear this a lot, and in my psychology degree there were a number of students who thought that surveys were the bee’s knees when it comes to testing theories.  “Especially anonymous surveys,” they would say.  “You can always trust an anonymous survey.”

Over time, and after many fruitless attempts at scientifically arguing against this, I’ve found the most compelling counter-argument is a very simple example about – wait for it –women’s sex lives.  A New Scientist study asked women aged 18-25 how many sexual partners they had had.  However, to make things interesting, the women were broken into three groups:  those who thought their answers would be read, those who thought they would be anonymous, and those who were hooked up to a (fake) lie detector.

Women who thought their responses might be read said they had had an average of 2.6 sexual partners. Women who thought their answers were anonymous said they had had an average of 3.4 partners.

And women on the fake polygraph?  4.4.

Hardly conclusive, but great dinner-party fodder if you ever meet an experimental economist.