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 Freakonomics radio.

It's that moment every couple of weeks.

We talk to the co-authors of the book and the blog of the same name.

It is the hidden side of everything, of course.

And today, it is the brains, if you will, of the operations.

Stephen Levit, Professor of Economics at the University of Chicago.

Good to talk to you again.

Oh, thank the guy great to be here.

So listen, usually when we have you on and dubners out doing whatever it is that he does,

it's because you have some new research you want to share, some big project you're working on.

But yet this time, it's different.

It is. Now we're trying to get you in on the ground floor.

And here's the question we're thinking about.

Periodically, everyone faces really difficult, important questions in life.

Should you move to a new city or quit smoking or maybe what caused a terrible disaster?

What caused a tender? I don't know.

Should I get a tattoo?

And there are pros and cons.

Wait, wait, do you have a tattoo?

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