Hey there, it's Stephen Dovner, and before we get to this bonus episode, a quick offer.

If you happen to be a member of 24-hour fitness, the National Gym Chain,

and you want to be part of a behavioral science experiment, go to 24go.co-freeq.

That's 24go.co-freeq.

You can enroll there in a program called Step Up, which was created by our friends at

Behavior Change for Good. That's a group of scientists who are running big experiments to help people

achieve better outcomes in health, education, and personal finance. You've heard about their work

in a couple previous episodes. One was called How to Launch a Behavior Change Revolution.

The other was, could solving this one problem solve all the others. The deadline for Step Up

is January 31st, so hurry. Again, it's 24go.co-freeq. That's 24go.co-freeq.

Now, on With Our Show.

This is a Freakinomics Radio Extra, our full interview with the entrepreneur and Dallas

Maverick's owner, Mark Cuban, who's been appearing in our Hidden Side of Sports series.

Cuban has owned the Mav since 2000, and he's one of the investors regularly appearing on the

reality TV show Shark Tank. He made his fortune in the late 1990s, selling the streaming service

broadcast.com to Yahoo for $5.7 billion. Our conversation took place last summer before the current

NBA season had begun. LeBron James was still a free agent at the time. The Mavs had already drafted

the Slovenian teenager Luca Dončić, who's been having an excellent rookie season, even though

the Mavs are doing poorly overall. The conversation covers a lot of ground, including Cuban's ambitions

to own a baseball team, and maybe, just maybe, his ambitions to run for president. You'll also hear

a number of names that you may not be familiar with. Byron Wizard White, for instance, was a great

collegiate athlete who played three seasons in the NFL, twice leading the league in rushing,

...