From APM, American Public Media, and WNYC.

This is Freakonomics Radio on Marketplace.

Here's the host of Marketplace, Kyra's Doll.

Time now for a little bit of Freakonomics Radio that moment in the broadcast every couple of weeks

where we talk to Steven Dubner, the co-author of the books and the blog of the same name about.

Wait for it. Wait for it. Yes, the hidden side of everything. Dubner, how are you?

I am great. I love the holidays.

Everybody starts to feel charitable toward our fellow humans.

Let me ask you this, Kyra, if you had to guess, how would you say that economists rank on the scale of charitable giving?

Zero. Zero. Is there a number that I could throw out there?

Let me, you know, we do think of economists as a little bit more self-interested than average.

Let's say there is a lab experiment that's known as the dictator game that we're...

It's meant to test charitable giving between strangers.

And one of the best predictors that one person will give zero of their money to another person is if that person is an undergraduate economics major.

Yeah, it's all... Yeah, it's the understanding the incentives thing, man. It doesn't surprise me at all.

Exactly. But let me say this. In Freakonomics Radio's ongoing efforts to understand the creature known as homoeconomics,

because we have uncovered evidence in the wild, mind you, that the species may in fact be evolving.

There is a British economist named Martin Brooks. He works at a hedge fund.

And for some time, he had been interested in bringing a more data-driven approach to philanthropy.

And then one day, his phone rang.

A big UK charity called Banados, which is a children charity, rang me up and said, could they borrow an economist from me?

Because they didn't know where to find them, and they couldn't afford to hire one, even if they did know where they'd find them.

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