Like many people, I looked at Nate Silver’s model for the presidential election outcome daily for the last six months. I hoped it would calm me down. It didn’t. I was not calm because his model was predicting somewhere between pretty close and extremely close the whole time, unlike during the 2012 election. Here’s what it looked like on election day–the blue line was the probability that Hillary Clinton would win and the red line was the probability that Donald Trump would win:

538-graph-election-day

A lot of people seemed to have looked at this and decided that Trump had very little chance of winning. That’s not what it says at all, and I think this points to a problem with our math curricula.

We could and should but do not have any kind of grasp of probability by the time we graduate high school. We need the education, because our brains have trouble taking base rates adequately into account. (See the second blurb here for a little more information.) We spend a lot of time learning algebra, which is for a normal person useful only for internalizing arithmetic and for the general brain workout, but we spend almost no time learning about probability. So we have an electorate swung in part by those living in genuine fear of being killed in a terrorist attack, which is a near-zero percent probability, and by those who were¬†blas√© about Trump’s chances of winning.

Basic probability is not hard to learn. Any teenager of average intelligence and a week of Dungeons & Dragons under their belt could have told you that Trump could easily win the election. The worst his chances ever got were about the same as rolling a 1 on an 8-sided die. It’s not great odds, but you don’t bet the life of your character on it, much less the fate of your whole game. And that’s the worst it got. It looks like he averaged around the chance of rolling a 1 on a 4-sided die. That happens a lot. Give it a try.

I’d love to see algebra classes replaced entirely by statistics classes, but I’d settle for replacing the first two weeks of Algebra I with an intro to dice gambling. The idea that knowing how to factor polynomials is more important than a real grasp of probability is hurting us.