What are the Odds? - Part 2

Back in July 2009, I noted that a man in Serbia, Radivoje Lajic, had just experienced the sixth meteorite impact on his home.  Mr. Lajic concluded that aliens were targeting his domicile.  I suggested that the odds of this happening by chance were about one-in-one quadrillion and concluded that one could not reject his hypothesis on purely statistical grounds.  It turns out I probably overstated the odds.

A coworker of mine, Aaron Betz, recently sent me an article in Wired from 2013 that gave the odds of being hit by any given meteorite at one-in-3,921,910,064,328.  The math can be found here.  Now this is only the probability for a single meteorite and literally thousands of objects impact the Earth's atmosphere every year.  However, best estimates are that only about 500 or so are large enough to leave a substantial meteorite.  If the typical person lives to age 80 that lowers the odds of having your home hit by a meteorite sometime during your lifetime to one-in-3379.  The probablility of being hit six times is 1:1.488 septillion (1.488E+24).  So, yes, the aliens are trying to kill the poor man!

On a related note, a man from Ohio, Gregg Nigl, managed the first perfect prediction for the first two rounds of the NCAA basketball tournament.  If the odds of any team winning a game in the tournament were 50/50 then the odds of pulling off Mr. Nigl's feat with a random guess would be 1:281 trillion.  The odds of a perfect prediction of all 63 games would be 1:9.223 quintillion (9.223E+18).

Of course the odds for any given game are NOT 50/50, so a perfect bracket is not as unlikely as that.  But still,...  Duke mathemetician, Jonathan Mattingly, has taken this into account an calculates that the odds of a perfect bracket are about 1:2.4 trillion, or about 3.8 million times more likely than the 50/50 odds.

Now you might think that these are really long odds, but lots and lots of people are filling out NCAA brackets each year so the odds of at least one of these people getting a perfect bracket must be pretty high.  Well there are 7.5 billion people in the world.  If each person in the world filled out a different bracket, then the odds of a perfect bracket amoung those 7.5 billion entries is 1:320.  Put another way, it would take 160 years of NCAA tournaments before the odds of a perfect bracket rise to 50 percent.  So don't hold your breath waiting.

For comparison purposes the odds of winning the Powerball jackpot on any given drawing are 1:292,201,338.

To summarize:

• You are 8200 times more likely to win the Powerball jackpot than you are to fill out a perfect NCAA bracket.
• You are 620 million times more likely to fill out a perfect bracket than you are to have your home hit by a meteorite six times.