The Cobra Effect

Season 4, Episode 4

If you want to get rid of a nasty invasive pest, it might seem sensible to offer a bounty as a reward. But the problem is: nothing backfires quite like a bounty. In this episode of Freakonomics Radio, we look at bounties on snakes in Delhi, India; rats in Hanoi, Vietnam; and feral pigs in Fort Benning, Georgia. In each case, bounty seekers came up with creative ways to maximize their payoff – and pest populations grew. Stephen Dubner and Steve Levitt talk about how incentives don’t always work out the way we expect them to. Later in the hour, if you want to write a book about Winston Churchill, you are going to have to pay. The Churchill estate is intensely protective of Sir Winston’s copyright, so much so that if you write a book about him, you are likely to go into the red. Stephen Dubner talks about who owns words, and what it will cost you to write a book about Churchill.

The Cobra Effect: A New Freakonomics Radio Podcast

Our latest  Freakonomics Radio podcast is called “The Cobra Effect.” (Download/subscribe at iTunes, get the RSS feed, listen via the media player in the post, or read the transcript below.) The gist: when you want to get rid of a nasty pest, one obvious solution comes to mind: just offer a cash reward. But be careful -- because nothing backfires quite like a bounty.

This is a story-filled episode that looks at the unintended consequences of trying to control everything from traffic to rodent populations to dangerous gases. If you've been hanging around these parts for a while, you will have noticed a similar theme in our "Misadventures in Baby-Making" podcast or the section of the film Freakonomics wherein Steve Levitt tries to potty-train his daughter.

The episode begins with Vikas Mehrotra, a finance professor at the University of Alberta, who is visiting Bogota, Colombia, and notices a strange traffic pattern. (You may remember Mehrotra from our "Church of Scionology" episode.) If you want to do some further reading on the story Mehrotra tells, check out “Rationing Can Backfire: The ‘Day Without a Car’ in Mexico City” (abstract; PDF) and “The Effect of Driving Restrictions on Air Quality in Mexico City” (abstract; PDF).