A few days ago, Republican pollster Kristen Soltis Anderson published a post at her blog on the efficacy of polls so far. The following day, the Iowa Poll (by the Des Moines Register and Bloomberg) and the CNN/ORC poll each came out with contradictory pictures of where Republican voters in Iowa are headed. In one sense, the two polls were on the same page: Republican voters are headed down the road towards embracing a kind of ugly neo-fascism. Just which ugly neo-fascist they're embracing is where the problem comes in. The Iowa poll is ready to bury Trumpf. The CNN poll has him ruling the roost.The CNN poll shows that likely Republican caucus participants are more in thrall to Trump than ever and with plenty of momentum:
• Trumpf- 33% (up 8 points)• Cruz- 20% (up 9 points)• Dr. Ben- 16% (down 7 points)• Rubio- 11% (down 2 points)• Poor Jeb- 4% (down 1 point)• Fiorina- 3% (down 1 point)• Rand Paul- 3% (up 1 point)
The rest of the candidates aren't worth mentioning since their percentages are too far below the margin of error to give any semblance of accuracy. But the Iowa Poll shows a very different story at the top.
• Cruz- 31% (up 21 points)• Trumpf- 21% (up 2 points)• Dr. Ben- 13% (down 15 points)• Rubio- 10% (up 1 point)• Poor Jeb- 6% (up 1 point)• Christie- 3% (up 2 points)• Huckabee- 3% (no change)• Rand Paul- 3% (down 2 points)
Back to Anderson, she decided to tackle two questions-- are these polls we've been looking at all year predictive and are they valid? In terms of predictive, she's entirely dismissive. "Early polls," she wrote, "are not really 'predictive,' especially not in a volatile race. In one sense, with only a month and a half until Iowa, it feels like we are incredibly close to the first caucus. However, with about half of GOP voters saying they haven’t fully decided on a candidate, this is still a race very much in flux... Most horse-race polling is not terribly predictive precisely because it gives you a snapshot in time, and that time is still many days away from Iowa. The ground is always shifting beneath us; of course a poll today isn’t 'predictive' of what will happen a month and a half from now." OK, makes sense and then she gets to the heart of her point: "What I want to explore instead is the question of validity: 'Is Trump REALLY the frontrunner, right at this moment? If the election WERE held today, would Trump really win? Are the polls right, and are they a valid picture of this point in time?'"
Here are the factors to consider when assessing “are the polls telling the truth about what’s going on in the GOP primary?”1) Are these polls actually capturing “real” Republican primary voters?Here’s how most of these national media polls work: they start off calling around a thousand adults across the country. Of the thousand adults who participate in the poll, about 800 or so will report that they are a “registered voter.” Then, those people will be asked to identify with a party, or, if they are independent, which party they “lean” toward supporting. From that, these media polls wind up with a bucket of 300 to 450 people who say they are registered to vote and that they either are Republican or are an independent-leaning Republican.These are the people who are then asked: “If the election were held today, for whom would you vote?”The reality is that most of those people will never actually make it to the polls.Let’s take Florida in 2012, where there were roughly 4 million registered Republicans in the state on the eve of the primary. Only Republicans are allowed to vote in Florida’s closed presidential primary. Fewer than half participated in the state’s presidential primary that year. A poll of all Florida Republican voters would have had a sample where about half of the people who responded never actually showed up to vote.Now, we do know that people who take polls are slightly more likely to be politically engaged, so the mere fact that someone is actually taking the time to chat with a pollster does mean they are more likely to be an actual, honest-to-goodness likely voter. But still…there are a lot of people responding to the polls who are never going to set foot inside a voting booth come next spring.The assumption here from those who think Trump’s numbers are inflated is that by casting a very, very wide net with these polls, people who are not committed, “base” Republicans are being swept up into the subsample and that it is those people who are boosting Trump’s numbers. (There is plenty of data to suggest that Trump voters are less likely to vote than others.)The prescription therefore would be to only survey those who have a proven track record, on the voter file, of participating in things like presidential primaries. (Or, alternatively, a method like the one used by Adrian Gray, someone I consider to be one of the brightest minds on the right, who starts with casting that wide net and surveying all New Hampshire Republicans, but also provides crosstabs of “likely” and “very likely” voters, allowing folks like you and me to see how different turnout scenarios might lead to different results.)The upside to much more tightly screening respondents is that you weed out people who are unlikely to show up and theoretically hit a target that is much closer to the mark than “let’s just survey everyone and see how it goes.”But there is a downside to tight screening.Consider the odd coalition that Trump has assembled; Trump’s support does not appear to stem from any traditional “faction” of the GOP. For instance, he’s not overwhelmingly beloved by the tea party, the very conservative and the evangelicals, who tend to favor Cruz and Carson. Nor is he anything remotely close to an “establishment” pick. His support doesn’t come from any one group we think of as a “likely voter” bloc, but instead comes from people who are less educated and watch more television.But you do hear the constant refrain from Trump supporters that he’s “energizing them” in a way nobody has previously. Furthermore, the blockbuster viewership numbers for these Presidential debates and the fact that the field is so large, so fractured, and that Trump is drawing so much attention to the contests, could very well mean that our definition of “likely voter” needs a re-think.In 2008, Barack Obama won the Iowa caucuses in part by re-making the electorate. Screen too tightly for likely voters based on past participation, and you can easily miss out on someone changing the game and bringing new people into the process.It’s certainly the case that Trump’s supporters don’t necessarily look like “likely voters” as we know them. But it’s not impossible to think that Trump could re-shape what it means to be a “likely voter.” This is, after all, a very strange election indeed.2) Are people just SAYING they like Trump, but when it comes down to it, even if they go vote, they won’t REALLY choose him in the voting booth?As we consider this question, let’s assume the people we are surveying are, generally, the right people. We then have the question of whether or not people lie (or, to be more charitable, misrepresent their views), and whether or not people who say they are voting for Trump really do mean it.This always comes up on questions where there is “social desirability” bias, where respondents feel pressure to give an answer that is considered socially acceptable rather than tell the unvarnished truth about what lurks in their hearts and minds.Harry Enten at FiveThirtyEight breaks out the polls, both nationally and in early states, and finds that there is a significant difference in Trump’s level of support when polls are done online or via “robopoll” versus with a live-interviewer. We call this a “mode effect,” where the result of a survey seems to be influenced by the method through which it is conducted.In general, Trump does better when respondents don’t have to actually tell another live human being that they plan to vote for Trump.Which, then, is the more accurate approach for gauging voter sentiment? It may depend on the nature of the contest you’re polling.In New Hampshire, voters will disappear into a voting booth and select their choice for the nomination. They won’t have to tell another soul if they voted for Donald Trump. In this case, the fact that respondents in an online poll also get nearly perfect anonymity may more closely mirror the actual act of voting.But in Iowa, or in other caucus states, the selection process will involve discussion and a public airing of one’s preferences. In that case, telling someone live over the phone how you feel may be closer parallel to the caucus process.All of which is to say that we may have a few different factors in play here: some people may say they plan to vote for Trump but, in reality, they haven’t had to deeply consider the question and so they just say the last name they heard on the news. However, some people may be afraid to say they support Trump, but in the privacy of a voting booth would make that preference known with their secret ballot.Trump’s support may be overstated because we’re far enough out that people haven’t thought hard about their vote, and when online, people are more comfortable picking the person who amuses them rather than the person who would be Commander-in-Chief. But Trump’s true support level may be understated by live-interview polls if people feel that voting for Trump is a socially unacceptable behavior they nonetheless plan to engage in....I don’t know if Donald Trump will be the Republican nominee.Every day we get closer to Iowa, and Trump stays well ahead in the polls, I suppose to odds of that outcome do increase. There are also a number of reasons why it might not come to pass. People could change their minds, Trump could finally say something that pushes his supporters away (I’m not holding my breath), another candidate could become unbelievably compelling after a strong debate performance, a bomb could go off somewhere and reshape our national dialogue, someone’s Super PAC could drop a kajillion dollars onto the airwaves and re-arrange the race, etc. etc. There are a ton of unknowns and fifty-some days until the Iowa Caucuses.But I also think it is important for us to separate out the “predictive” quality of these horse-race polls (they are not really predictive, despite everyone loving to use them as a forecasting metric) and the “validity” measures that give us reason to believe or doubt polls as they stand today.When deciding if you “trust” the polls, I would encourage people to stop worrying about whether these polls are predictive, because they really aren’t. I do think we need to be very critical about whether or not these polls are valid measures of this current snapshot in time, and I think there are important questions to be raised on that front.
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