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The perfect bracket: Mathematician talks longshot odds of predicting March Madness

Jeff Bergen
According to mathematics professor Jeff Bergen, the odds of predicting a perfect bracket in this year's NCAA men's basketball tournament are one in 9.2 quintillion. (DePaul University/Jeff Carrion)
As college basketball fans get set to fill out their brackets for this year's March Madness, mathematics professor Jeff Bergen offers some perspective on the odds of creating the perfect bracket. It's more likely, says Bergen, to predict the winning party in the next 62 presidential elections through the year 2264 than to pick all 63 games correctly in this year's NCAA men's basketball tournament.

Using a standard bracket that asks fans to predict the results of 63 games played from mid-March to early April, Bergen determined that someone filling out a bracket has a one in 9.2 quintillion -- or more accurately one in 9,223,372,036,854,775,808 -- chance to predict the correct results of each game. He reached his answer by raising two, as in the number of possible winners in each game, to the 63rd power.

"The thing that makes March Madness so interesting to me is that the person who watches college basketball until four in the morning really doesn't have a better shot at a perfect bracket than someone who doesn't watch college basketball at all," says Bergen.

To emphasize further his point of just how unlikely it is to predict a perfect bracket, Bergen determined some other hard to imagine occurrences that are more likely to happen:
  • Winning the Powerball and Mega Millions lottery in the same week by buying one ticket each for both.
  • Picking six people at random on the street and all of them having the same birthday as you.
  • Your favorite professional baseball or football team winning the next 12 championships.
  • A professional golfer getting a hole-in-one on five consecutive par 3 holes. (They average around one in every 2,500 attempts.)
  • A professional bowler rolling 85 strikes in a row. (They roll strikes about 60 percent of the time.)
To put the number 9.2 quintillion into perspective, if you piled that many brackets on top of each other, they would reach from here to the sun and back more than 3,000 times.

Bergen realizes that many may look at his calculations and think they have a better chance at a perfect bracket because they follow basketball and the annual tournament closely. However, knowing that a No. 1 seed has never lost to a No. 16 seed, or that a No. 2 seed has only lost to a No. 15 seed eight times in 128 opportunities can only help so much, he says. With tournament knowledge like that, the odds of picking a perfect bracket only increase to about one in 128 billion, Bergen adds.

"I don't want to come across as a mathematician trying to ruin the fun of March Madness, though," says Bergen. "The idea is to have fun, even if you probably aren't going to get a perfect bracket. Usually you just want to do the best out of your family or a group of friends. Just enjoy the games and comradery.

"I've been a sports fan for a really long time, so I don't mind playing with these crazy numbers," says Bergen. "People get fascinated with the magnitude of the numbers, but the math is not that complicated. It's just bigger numbers than we usually come across in daily life. I would like to demystify how I got the 9.2 quintillion answer because it would be nice if at every middle or high school the students were coming up with this answer."

Nicknamed March Madness due its often-unpredictable nature, the NCAA Tournament begins March 14 with the "First Four," which features four games not included in traditional brackets, to trim the 68-team field to 64. The announcement of the 68-team field is set for March 12. The Final Four begins April 1 with the national championship game held April 3.

Watch Bergen break down the numbers at http://depaulne.ws/MarchMadness_2017.