A Mind for Madness

Musings on art, philosophy, mathematics, and physics

The Myth of a Close Election

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Before presenting the argument for why the current US presidential race is not as close as it seems, let’s first get out of the way some of the major reasons why it seems close. First, there is the bias of the media. What is more exciting: watching a photo finish win of .01 seconds or watching someone take the lead early and never give up ground?

All of our news sources have a vested financial interest in portraying the presidential race as close. It keeps people coming to their webpages or turning on the news to see how things have changed. The myth was created because it sells. But this is far, far from the only reason someone would want to keep this myth alive.

If your candidate is the one that has the bad odds, then you will want to portray the race as close to keep up hope. No one wants to admit (or even believe) that they are going to lose. This is about as old and established a cognitive bias as you can find. What about if your candidate is the one that is ahead? Well, there is very good reason to portray the race as close in this case as well. If all the people that are going to vote think it is an easy win, the turnout may go down causing a sudden upset that shouldn’t have happened.

This gives good reason for even non-news sources to keep up the impression that it is a close race. In fact, I can’t think of any reason someone would not have some interest in skewing the numbers to make the race seem closer than it is. In our weird system of the electoral college, it is actually quite easy to keep this myth up. You just give standard national polling data. All of a sudden it looks like a dead even match. One day one candidate is up, the next day the other. Back and forth it goes. How exciting!

It turns out that the most careful analysis out there, Nate Silver at Fivethirtyeight, has as of yesterday a 79% chance of Obama winning and a 21% chance of Romney winning. Before discussing what this means, I’ll first point out that this is a true professional statistical analysis. He uses tons of polls in all of the states (sometimes 10 for a single state!) and not just one that suits his purpose. He takes into account noise and how historically accurate the polls have been at different times leading up to the election. It is a fully developed statistically model (as opposed to places like Real Clear Politics which takes straight from polls without filtering through a model).

He has used his methods in predicting sports and elections in the past and has an impeccable track record for accuracy. Now that that is out of the way, what do the numbers mean? Well, they mean what they say. A better tactic is to point out what they don’t mean. A 79% chance of a win is not a sure thing. In fact, people go to Vegas and play odds much, much (much, much) worse than 21% and win! Does this mean they had better odds than predicted? No. It means sometimes you win when you have .0001% chance at winning.

This is statistics we’re talking about, so there is never any sort of guarantee. If Romney wins, will Nate Silver be wrong? No! And that is the crucial point. If every time Silver gave 79/21 odds, the person with the 79% chance of winning won, then that would definitively prove Nate’s model incorrect. In order for the model to make accurate predictions it turns out that 21% of the time that he makes this 79/21 prediction, the person with the 21% chance of winning has to win.

You can go to his blog and check out his methods for yourself, but his track record should give us a bit of confidence that he knows what he’s doing. Now back to the original question: Is the US presidential race close? Armed with these stats, the answer is subjective and you can decide for yourself. To me it would be a lie to say that it is some sort of blowout, but under no stretch of the imagination is 4-1 odds close. I’m not a betting man, but I’d easily take the occasional 4-1 odds, and that says to me that it isn’t a very close race.

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Author: hilbertthm90

I am a mathematics graduate student fascinated in how all my interests fit together.

2 thoughts on “The Myth of a Close Election

  1. I agree with your view, and found your explanation of statistics methodology informative. Nate does project a closer popular vote result, but of course the electoral votes determine the winner.

  2. Addendum: As of 9:30 pm Pacific time on election night, it appears Nate Silver’s model will have a 100% accuracy in his predictions. This is a true testament to the power of math!

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