Sunday, August 25, 2013

Some thoughts about election prediction.


It's been nearly two weeks since there has been any new data on the New York City mayoral race. The last few polls agree the three at the front of the pack are Christine Quinn, Bill De Blasio and Bill Thompson. Unless one of them gets over 40% of the vote, and the recent polls make that look very unlikely, the top two will go into a runoff election, and the odds make it look like an uphill climb for Thompson.

The New York Times endorsed Quinn. Her bio is certainly compelling from a progressive standpoint. She would be the first female mayor of America's largest city and she would be the first openly gay mayor. Her record on the issues is not as compelling from a progressive standpoint. She is seen by many as a person who would continue the Bloomberg status quo. The Nation, a truly progressive periodical unlike the Times, has endorsed De Blasio.


Nate Silver has published numbers saying that history favors the long term front runner of the year, which would be Quinn in this case. She had competition from Anthony Weiner after he announced and before his spectacular crash, but for months before that she lead in every poll.

This is one of the many places in predictions where I part company with Silver. I assume that every election stands on its own and historical data should not outweigh current polling.

It's impossible to predict the big events and impossible to gauge the weight they will have. It looked like based on name recognition Anthony Weiner was a serious candidate, but the Carlos Danger situation cut his support in half, his position plummeting from first to a distant fourth. A judge deciding "stop and frisk" was unconstitutional gave De Blasio a big boost, but it's hard to say if it's a surge or a bounce until we get more data. The Times endorsement should be much more important that The Nation's, but are either of them really events that make a difference in the polls?

I have no idea.

When I say that the last polls look like an overwhelming likelihood of a Quinn/De Blasio runoff, I am completely willing to say something else if the next polls change. It's very hard to say what events will change the polling numbers, known in journalistic circles as "moving the needle".

In 2012, Romney's 47% comments moved the needle against him, but he was already in a horrible position when he said that. Obama's awful first debate definitely moved the needle in Romney's favor, but by the time of the Biden/Ryan and the second Obama/Romney debate, the movement towards Romney had stopped and the tide reversed. He never was favored to win.

Conservatives hoped Benghazi would move the needle. It didn't.

Silver went to Princeton and I went to Cal State Hayward. Silver was hired by the Times and I haven't been able to get anyone to pay me for my work. In my favor, I did better than he did in 2008 and 2012. (He missed Indiana in the electoral vote in 2008 and two Senate races in 2012 that I got right. One of them he missed by giving weight to historical data, something I would never do.)

Here's the big difference between us as far as I'm concerned. My education is in pure mathematics and his is in applied.

Election prediction is applied math. I deeply distrust it and I wait until I think the data really means something. I have arbitrarily chosen about a week before the polls close. By then, I figure enough mail-in ballots have been cast that the most important proviso of any opinion poll is actually true, that "the election is being held when the poll was taken".

Is seven days the right number? Maybe ten would be better, maybe four. If my predictions become less reliable in the future, changing this time period is one of my first places to look to improve my system.

This brings me to something else Silver has done that I disagree with vehemently. He is predicting the make-up of the Senate in 2014 and giving a margin of error. These numbers are being used as scare tactics by the Democrats begging for money.

As far as I'm concerned, these numbers are worse than nonsense. He does actual work, so I am not happy comparing him to lazy, ignorant anti-intellectuals like Dick Morris, Karl Rove, Jim Cramer or George F. Will, but predictions about a multi-part election more than fifteen months away from polls closing are mere balloon juice. Even if someone "crunches numbers", given how many unknowable events there will be in the next year and a quarter means his work has no more meaning than doing exact bio-rhythms or a complete astrological chart.

I do not know if Nate Silver will ever read what I write. If he does, I want to say to him, older nerd to younger nerd, stop doing the stuff that is most likely to hurt your reputation. A fifteen month prediction about elections is no better than your work in fantasy football or Oscar prediction, which you have been gracious enough to admit has been less than optimal.

Wait until just before the election. Then the numbers of people doing actual work, work like yours and mine and Sam Wang's, have meaning. Right now, your work in 2013 is like Gene Simmons of KISS going out on a limb in 2011 predicting President Rick Perry and giving us as the reason to believe him, the quote "I'm never wrong."

He was wrong. Even with your margin of error, saying there is 95% confidence in your numbers is plain silly.

Stop being silly. You are much better than that.

Here endeth the lesson.

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