Archives for odds



What Are the Odds of Twins Born in Different Years?

The following is a guest post by Louise Firth Campbell and Amram Shapiro, the authors (with Rosalind Wright) of The Book of Odds: From Lightning Strikes to Love at First Sight, the Odds of Everyday Life.

Rare news stories recur with surprising regularity — one of these annual stories is the birth of twins in two different years. 

You can see the appeal to editors. Babies are photogenic, especially twins. The symbolism of the New Year as a baby which ages to dotage by year end is an old one, a staple of thousands of New Year’s cards. There is an interesting apparent time tension in the story. Twins share a womb and genomes. Yet a few seconds separation in time of birth makes an apparent year’s worth of difference.[1]  This event is considered a rarity and only a handful of cases are reported in the press each year. This rarity makes it news, but is the event really as rare as it seems?

Let’s start with the news in 2013/2014. If the cases reported in the North American media, two in the U.S. and one in Canada, are the only cases, these events are rare indeed. There are about 4 million births a year in the U.S. That would suggest these events are as rare as 1 in 2 million. Someone visiting the Grand Canyon is more likely to die by falling off the edge (1 in 1.5 million).[2]  That doesn’t feel right to us. Read More »



Why Online Poker Should Be Legal: A New Marketplace Podcast

In our latest Freakonomics Radio podcast, Steve Levitt visits with Marketplace‘s Kai Ryssdal to discuss his poker research and his personal poker history. The episode is called “Why Online Poker Should Be Legal.” You can download/subscribe at iTunes, get the RSS feed, listen via the media player above, or read the transcript below.

In case you haven’t been following the long-running legal story, here’s the gist. Online poker was growing fast in the U.S. until Congress passed the Unlawful Internet Gambling Enforcement Act of 2006, which pretty much shut things down. The ruling was based in large part on the government’s reasoning that poker is predominantly a game of chance as opposed to a game of skill.  But is this classification correct? Read More »



A $640 Million Lottery Jackpot and a Lot of “Skewness”

The press and the streets in the U.S. are buzzing today about the world record $640 million lottery jackpot that will be drawn tonight at 11pm in Atlanta, GA. 

This excitement is what economists call “skewness.” The odds of winning have been quoted as 175 million to 1 — yet all of us are hoping to be that one. We explained the irresistible appeal of skewness (and the lottery) in our Freakonomics Radio podcast “The No-Lose Lottery.” In that episode, we also introduced a new financial product called Prize Linked Savings accounts — an idea that utilizes skewness for saving. We also explained why lottery commissioners would probably hate it. Read More »



Congratulations, You’ve Lost! How Slot Machines Disguise Losses as Wins

Casinos are designed for a single purpose: to separate you from your money. And they’re good at it. Commercial casinos in the U.S. made nearly $35 billion in revenue last year, up a percent from 2009.

While they represent just a fraction of that revenue, slot machines are the casino gateway drug for the least savvy gamblers. It’s why they’re by the door. More than any other casino game, slots condition people to keep playing through positive reinforcement (bells and whistles). And the odds have gotten worse as technology has improved.

Though today’s sophisticated multi-line machines have a higher “win-rate,” the amount won is negligible, and often less than what was originally gambled. A recent study by researchers at the University of Waterloo in Ontario, finds that these multi-line machines are more effective than their single-line predecessors at taking money from the gambler by disguising losses as wins. Read More »