## Time to eat some crow. That prediction stunk. ~Nate Silver on Brazil Germany WC 2014 aka "Most Shocking Result in World Cup History"

#### Adam Rifkin stashed this in Nate Silver

**Stashed in:** Brazil, Math!, Soccer, So you're saying there's a chance...., Soccer, uh oh

Nate Silver confesses to his awful prediction:

We had Brazil favored to win Tuesday’s World Cup semifinal against Germany (even despite the absence of Neymar and Thiago Silva).

Time to eat some crow. That prediction stunk.

It’s not that a German win was all that unlikely. Germany had a 35 percent chance of victory, according to our model. But the 7-1 scoreline was truly shocking.

The Soccer Power Index (SPI) match-predictor (which uses a poisson distribution to estimate the range of possible scores) gave Germany only a 0.022 percent probability (about one chance in 4,500) of scoring seven or more goals. Likewise, SPI gave Germany a 0.025 percent probability (one chance in 4,000) of beating Brazil by six goals or more.

Statistical models can fail at the extreme tails of a probability distribution. There often isn’t enough historical data to distinguish a 1-in-400 from a 1-in-4,000 from a 1-in-40,000 probability. (This is the some of the basis of Nassim Taleb’s book “The Black Swan.”)

We can, however, at least confirm that the match was an extreme outlier from the standpoint of past World Cup matches. There have been 833 matches played since the World Cup began in 1930. Based on the scoreline, this was the most unlikely result.

Net net: it was an exceptionally bad game.

so, what he's saying is, miracles DO happen?

If the odds of something are 1-in-4000, that something will occasionally (very rarely) happen.

It just feels like a miracle when it does, but math probabilities do explain the outcome.

8:16 PM Jul 08 2014