Posts Tagged ‘Polls’

On Polls

Saturday, November 5th, 2016

Election season is upon us which means that poll-watching season is upon us. Back in 2012, I wrote a long post about the analysis of the polls. Specifically, I focused on the 2000 election in which Bush led the polls going in, Real Clear Politics projected a Bush landslide and … it ended in a massive recount and a popular-electoral split. I identified the factors that I thought contributed to this:

In the end, I think it was all of the above: they overestimated Nader’s support, the polls shifted late and RCP had a bit of a bias. But I also think RCP was simply ahead of its time. In 2000, we simply did not have the relentless national and state level polls we have now. And we did not have the kind of information that can tease out the subtle biases and nuances that Nate Silver can.

Of course, I wrote that on the eve of the 2012 election, where Obama significantly outperformed his polls, easily winning an election that, up until the last minute, looked close.

The election is now three days away which means that everyone is obsessed with polls. But this year, a split has developed. Sam Wang is projecting a 98% chance of a Clinton win with Clinton pulling in about 312 electoral votes. HuffPo projects a 99% chance of Clinton winning the popular vote. Nate Silver, however, is his usual conservative self, currently giving Clinton only a 64% chance of winning. So who should we side with?

To me, it’s obvious. I would definitely take Silver on this.

Put aside everything you know about the candidates, the election and the polls. If someone offered you a 50-to-1 or a 100-to-1 bet on any major party candidate winning the election, would you take it? I certainly would. I would have bet $10 on Mondale in 1984 if it was a potential $1000 payoff. And he lost by 20 points.

It seems a huge stretch to give 98 or 99% odds to Clinton, considering:

  • Clinton has never touched 50% in the poll aggregates.
  • There are still large numbers of undecideds and third party supporters who will doubtless vote for one of the two candidates (and Trump’s recent surge has come from fleeing Johnson voters).
  • We have fewer live interview polls now than we did in 2012.
  • As Nate Silver noted, the average difference between final polls and the election has been about two points.
  • Basically, I think Wang and HuffPo are not accounting enough for the possibility that the polls are significantly off. In the last 40 years, we’ve had one Presidential election (1980) where the polls were off by a whopping seven points. That’s enough for Trump to win easily (or for Clinton to win in a landslide).

    Moreover, Wang’s and HuffPo’s results seem in contradiction to each other. If Clinton really did have a 98% chance of winning, wouldn’t you think she’d get more than 312 electoral votes? That’s the kind of certainty I would expect with a pending landslide of 400 or 500 electoral votes. A 42-electoral vote margin of errors is *really* small. All you would need is for the polling to be wrong in two big states for Trump to eek out a win (note: there are more than two big battleground states).

    This brings me to another point. Pollsters and Democrats have been talking about Clinton’s “firewall” of supposedly safe states that guarantee a win in the electoral college. But that firewall is a fantasy. When Clinton dipped in the polls in September, suddenly numerous blue states like Pennsylvania and Michigan were in play. And, in fact, Silver projects a bigger chance that Trump wins in an electoral-popular split than Clinton because many of his states are safer. The talk about a “firewall” is the result of people becoming drunk on state-level polling. We have 50 states in this country. Statistically, at least one should buck a 98% polling certainty. There are only twenty states that Real Clear Politics rates as “leans” or “tossup”. Statistically, at least a couple of those should buck the polling.

    Here’s another way of thinking about it. There have been 56 elections in American history. If Clinton really were a 98% or 99% favorite, a Trump would be the biggest upset in American electoral history. I find that claim to be absurd. Bigger than Dewey and Truman? Bigger than Polk’s election? Bigger than Kennedy’s? Bigger than Reagan turning a close race into a blowout?

    I should point out that having long tails of probability also means there is a greater chance of a Clinton landslide. That’s possible, I guess. But, admitting to my priors here, I find a Trump upset more likely than a Clinton landslide. Clinton is deeply unpopular with large parts of the country. She’s not popular with young people. Here in State College, Clinton signs and stickers are few and far between. This was not the case in 2008 and 2012, both of which were won handily by Obama. I really don’t see a Clinton landslide materializing, although I’ll cop to it if I’m wrong about that.

    Prediction is hard, especially about the future. I think a basic humility requires us to be open to the idea that we could be badly wrong. And 1-2% is way too small a value to assign to that. I think Clinton has the edge right now. But I would put her odds at more like 2-1 or 4-1. And I will not be shocked if Trump pulls this out.

    Because it may be a cliche. But there’s only poll that counts: the one taken on Tuesday.

    Update: One of my Twitter correspondents makes a good case that the variations in the polls are less reflective of changes in candidate support than in supporter enthusiasm. In the end, the election will come down to turnout — i.e., how likely the “likely” part of “likely voters” is.

    Mathematical Malpractice Watch: Admiration Edition

    Saturday, December 31st, 2011

    Gallup and USA/Today need to be beaten with sticks and sent back to remedial stats class. Most of their work is fine. But every year we get another useless poll about the most admired people in America.

    President Obama and Hillary Rodham Clinton are the nation’s most-admired man and woman — again — in the annual USA TODAY/Gallup Poll.

    Each leads their category with 17% of votes in top 10 lists that favor the most familiar names in global politics, religion, entertainment and culture.

    Does this strike you as being meaningful? For 83% of Americans, Barack Obama is not the most-admired man. The #5 man in the poll is Warren Buffett with … 2% of the vote.

    USA Today and Gallup have run this piece of trivia for half a century, using an open-ended unconstrained plurality. As such, it always puts whoever is most famous — usually the President — at the top of the list. Even in years where George W. Bush would’ve lost an election for Republican dog-catcher, he was still the most admired man because no one else was as famous or as in the news.

    Unconstrained pluralities are the most useless poll imaginable. They always produce embarrassing or useless results like this. We get this crap with “what issue is most important to you” polls as well, where they’ll say the second most important issue is, say, abortion, when abortion gets about 6% of the vote.

    A more valid way would be to give people a list of potentially admirable people and ask if they admire them. That would be useful and unbiased. Gallup wants to keep it “unprompted”. Fine. Conduct an initial poll, then make the list from the top 100 names on it.

    Polls are created news. They don’t tell us anything and are used to lead a slow news day. But this poll is especially useless. And yes, I said it when Bush topped the poll too.

    Trump Birtherism and 2012

    Wednesday, April 27th, 2011

    Now that Obama has released his long form birth certificate, will this silence the conspiracy theorists? Of course not. But it may turn the disturbing trend we’ve seen in recent polling data showing up to 47% of GOPers think Obama was not born in his country.

    The usual caveats to those polls apply. Most people are not political junkies and so haven’t followed the birther issue closely. Most Republicans don’t like Obama and so thinking he was born elsewhere is a good way of filing him into that “other” category. And many Democrats embraced the “Bush allowed 9/11” theory.

    But still, 47% is crazy. How did we get to that point?

    We got there because the mainstream GOP was playing footsie with the radical rump of the party. Everyone in the GOP power circles knew Obama was born in the US. But they were more than happy to let the issue fester — and occasionally poke it — because they knew it excited a small but motivated group of voters. They knew that stomping on the birther thing could split off some radicals. But most of all, it was a way to deligitimize Obama in the eyes of the voters. By not embracing but not rejecting birtherism — uttering such non-denials as “I take him at his word” — they kept the issue up, maintaining their ability to portray Obama as someone alien to America.

    And then it suddenly blew up in their faces. A shameless attention-whore reality-TV star came along and grabbed the issue with both hands. (Actually, now that I’m a fan of Maggie McNeil’s blog, I think it’s an insult to whores to compare Donald Trump to them.) Donald Trump didn’t embrace the birth certificate issue because he believed in it. He embraced it because it brought instant media attention. And suddenly the cancer of birtherism exploded all over the GOP. The environment became so toxic that no one who had political ambitions wanted to get in the pool.

    Don’t think so? Why are so many candidates reluctant to throw their hats into the 2012 ring? Even Palin is stalling and taking her time. Why is the presidential field so lackluster so far? Because none of the politicians wanted this on them. None of them wanted to run in a field where birtherism would be an issue and they’d end up at the head of a truly ugly campaign.

    The release of the birth certificate may turn the tide on this. Trump, of course, is claiming credit for the release of the BC and the vilest of the birthers are shouting, “why did it take so long” instead of “Boy, is our face red!” Trump is also moving on to more aggressively racist rhetoric such as telling Obama to stop playing basketball and implying he got into the Ivy League on affirmative action (because we all know how many AA guys become editors of the Law Review and graduate magna cum laude).

    But, personally, I don’t the GOP is going to get out of this that easily. They’ve been outfoxed, again, by the supposed amateur in the White House. They let the birther issue fester until Trump detonated it. And now that the birthers have been shown to be fools, the stink is going to cling to them for a long time.

    (Don’t think that I’m letting Obama off here. My understanding is that he could have done this at any time over the last two years. To drag it out this long hurt the country even though it hurt his opponents more. And, I’m sorry, when you apply for the job as President, you don’t get to hold back records like this.)

    Update: Thinking about this some more, the release of the BC is actually a huge political coup for Obama. The timing makes it seem (and it certainly being claimed) that Trump is the one who got this done. This cements Trump’s hold on the birther contingent and may even vault him — until the time comes to release his financial records — into front-runner status. And if THAT is the case, Obama just won the 2012 election. Because his opponent will either be Trump or a Republican maimed by Trump’s stupidity.

    Update: Several legal experts are pointing out that Obama could not release the certificate under Hawaiian law. While this is true, he clearly got an exemption now, according to the letter from his lawyer. That should not have taken two years.