FiveThirtyEighter Nate Silver Answers Your Questions About Politics, Baseball, and The Signal and the Noise
We recently solicited your questions for Nate Silver regarding his new book The Signal and the Noise: Why So Many Predictions Fail — But Some Don’t. Not too surprisingly, a lot of the questions were about politics and baseball. Below are Nate’s answers to some of them. Thanks to him for playing along and to all of you (as always) for sending in the excellent questions.
Q. Under what circumstances will a voter actually change his/her mind about whom to vote for? I understand that this rarely happens (this study for example), and that most of the action involves undecided voters deciding whom to vote for.
Also, if political scientist are right that voters rarely change their minds, how can a large swing in the polls ever occur? A classic example that your briefly mention in your book is that of Michael Dukakis, who was ahead of GHW Bush by 10% at one point in 1988. -Alan T
A. We see more big shifts in the primaries, when voters don’t have that much information about the candidates. Dukakis was a relative unknown at the start of the 1988 race, before the two parties could advance their own narratives. You rarely see big swings in voter conversion in late stage presidential races, though. If I knew how to cause such a swing, I’d be drawing a big salary from one of the campaigns right now. Read More »
Nate Silver first gained prominence for his rigorous analysis of baseball statistics. He became even more prominent for his rigorous analysis of elections, primarily via his FiveThirtyEight blog. (He has also turned up on this blog a few times.)
Now Silver has written his first book, The Signal and the Noise: Why So Many Predictions Fail — But Some Don’t. I have only read chunks so far but can already recommend it. (I would like to think his research included listening to our radio hour “The Folly of Prediction,” but I have no idea.)
A section of Signal about weather prediction was recently excerpted in the Times Magazine. Relatedly, his chapter called “A Climate of Healthy Skepticism” has already been attacked by the climate scientist Michael Mann. Given the stakes, emotions, and general unpredictability that surround climate change, I am guessing Silver will collect a few more such darts. (Yeah, we’ve been there.) Read More »
By last Friday, New York City was in full-on hurricane panic mode. Public transportation was scheduled for a Saturday shut down, stores were selling out of batteries and flashlights, windows were being taped, sandbags stacked; three-hundred and seventy thousand people were evacuated. This was going to be bad, the local media kept telling us. Really, really bad. Even the number-crunching, data-driven Nate Silver got in on the action, posting an extensive piece on his fivethirtyeight blog that if Hurricane Irene got close enough to New York City, it could be the costliest natural disaster ever. And by Friday, it was heading straight for the Big Apple.
By midnight on Saturday, things (in the words of NBC anchor Brian Williams) were “getting a bit sporty” in NYC. Wind was gusting, rain was coming sideways. The streets were empty, save for dozens of intrepid local TV news reporters deployed throughout the city, standing ready to report on the impending damage. Which, remember, was going to be bad.
The center of Irene hit New York around 9am Sunday. Winds reached 65 mph, the strongest in 25 years. By 10 am, the worst was over. No hurricane-shattered skyscraper windows, no preemptive power outages, no real flooding to speak of. The general tone among New Yorkers Sunday morning was, “That’s it?” But to watch the local TV news on Sunday, the storm had been epic. Rather than call in their battalion of reporters stationed around the area, the NYC TV news media kept reporting. All day. Read More »
OK, so Newt Gingrich’s senior staff have quit. But Newt’s not the news. At least according to the political prediction markets. The real news is that Texas Governor Rick Perry is likely to enter the Republican nomination race. The connection, of course, is that many of the staffers who quit have close ties to Governor Perry.
The figure below tells the story. (Click inside for graph). Since yesterday’s announcement, you can see the markets have re-evaluated Perry’s chances of winning the nomination from around 5%, up to 11%. There’s a tip here for newsgatherers: Focus on the details, and you’ll notice that the Perry’s prediction market rally began just after 11am. But the story broke three hours later, just before 3pm. Read More »
Nate Silver has (another) truly insightful post demonstrating the possible perverse advantage of receiving an 11th seed instead of an 8th seed in the NCAA tournament.
He explains: “[An average] team like Arizona would have a considerably better chance — about two-and-a-half times better, in fact — of winning its second round game and advancing to the Round of 16 as a No. 12 seed than as a No. 8 or No. 9 seed. This, of course, is because it has not yet had to face the No. 1 seed.” Read More »
Over at FiveThirtyEight.com, Nate Silver has a post attempting to debunk the idea that there is momentum in political campaigns. But I think he’s wrong. And his post provides a fun opportunity for a simple statistics lesson on the difficulty of discovering momentum. Read More »
| Polling guru Nate Silver has built a regression model, based on demographic and political trends, to forecast when a majority of the voting public in each of the 50 states might vote against a gay-marriage ban, or vote to repeal an existing one. His findings: by 2016, most states will have legalized gay marriage, […] Read More »