Stop Bashing Polls and Learn How to Read Them
(Bloomberg Opinion) -- Two new polls were released on Tuesday showing ….
Wait a second. You’re writing about polls again?
Uh, yes, and who are you exactly?
I’m the voice inside your head expressing all the objections to analyzing horse-race polls for presidential elections. So I repeat: You’re telling us about polls again?
Yeah, I am. What’s the problem?
To start with: We can’t trust the polls: 2016!
Actually … the national polls for the 2016 presidential election were pretty good. Just a bit off. In a few states, most notably Michigan and Wisconsin, the polls were wrong. I try to remind people that there’s always a margin of error and that polls are snapshots, not predictions. But beginning some 200 days out from the election, the polls start to be OK predictors of election results. They become more useful the closer we get to Election Day.
But it’s the Electoral College that matters, so if you have to write about polls you should stick to a handful of potential tipping-point states — Wisconsin, Florida, Michigan, Pennsylvania, maybe Arizona. The rest is garbage.
No. Despite the 2016 results, I still think the best way to go if you’re interested in the outcome is to follow the national polls.
Where’s your evidence?
State surveys have two big problems: A larger percentage of them are from lower-quality outfits, and there just aren’t enough of them. Remember, polls will be wrong for two reasons.
Some aren’t designed well; it’s like flipping a weighted coin that will average, say, 6 heads out of every 10. But even the best polls are subject to random error, just as if you flip a normal coin 10 times you can easily get 4 or 6 heads; you’ll sometimes get 3 or 7 heads; and you’ll even get more extreme results once in a while.
The power of polling averages is that it essentially corrects for random error, but only if there are enough surveys in the pot. So given the choice, I’ll stick with the far more plentiful national polls to get a sense of what’s happening. Especially since more of them tend to be high-quality efforts.
But we know that Donald Trump has an Electoral College advantage. You should adjust for that.
Not really. Trump had an Electoral College advantage in 2016, but Democrats had a bit of an edge in 2008 and 2012. If there’s a uniform swing — all the states shift the same amount — then Trump will still have an Electoral College advantage in 2020.
But we don’t know if that will happen. We don’t even know for sure that the shift in 2016 represented something real or if it was a fluke. Most analysts think it’s more likely that Trump has an Electoral College advantage than Joe Biden does, and perhaps even a larger one in 2020 than in 2016, but there’s nothing certain about it.
Focus on the national numbers, but keep in mind that they may translate into state results in surprising ways.
I bet you peek at the state polls anyway.
Guilty as charged. I also used to click on Gallup’s daily tracking poll every day before they discontinued it. I’m addicted. But we’re talking about normal people here, not me, and how to get a general idea of what’s going on. That would be from the national surveys.
This gets to the larger point. What I really wanted to complain about was the obsession with horse-race politics. We want substance!
Speak for yourself! Horse-race coverage is so dominant because, for better or worse, that’s what the customers want.
Perhaps. Wanting to know who will win seems pretty natural to me.
But it misses the whole point of politics. It encourages mindless cheerleading for the red team or the blue team, instead of serious discussion about what the election is about.
It doesn’t feel like that.
No, but that's what political scientists who study this stuff have found. And it makes sense if you think about it. How do we learn about policy questions that we're not personally involved with? Sure, some of us try to reason it out on some issues, but most of us, on most policies, learn from those we trust. And we tend to trust those we like — because we have shared membership in a group or political party.
But it shouldn’t be like that!
Says who? I don’t have the time to learn the details of the policy on Korea or on epidemiology. Or on what the Fed should do or what the deal is with whether we should really be honoring Christopher Columbus and on and on. And I study politics and government full time.
Mass politics — modern democracy — would be impossible if we all had to develop our own opinions about all of those things. Parties allow everyone to cast informed-enough votes without having to pretend to start from scratch every time.
Look: Of course the news media should report on government and public affairs, not just on elections. But election coverage is going to be focused on who is going to win, because that’s one of the main things people want to know. And responding to what people want doesn’t strike me as inherently undemocratic, to say the least.
Last question: Won’t this focus on polling discourage people from voting because they think it’s all over?
After 2016, it’s probably going to take a while for anyone to believe that a polling lead produces a certain win. Regardless, I’ll retreat here to the argument that, as a columnist and a political scientist, my job is to provide accurate information about important developments in U.S. politics, not to maximize turnout.
It still just seems wrong to be so obsessed with polls.
Remember: We’re talking about public opinion. What actual citizens think.
In principle, there’s no real difference between reporting the results of a horse-race poll and interviewing people in a diner and asking them what they think — something that almost no one believes is inappropriate. Of course, we want to know what our fellow citizens are saying and thinking.
In practice, polls have the advantage that survey research methodology can ensure that we’re getting a fairly accurate read on what people in general think. Indeed, good polling can set the context for good street-level interviews, since it can be a check against the instinct (by either reporters or readers) to believe that this particular set of people are typical of the nation as a whole. And good interview-style reporting, informed by the polls, can go in depth in a way that is harder to do in surveys.
This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.
Jonathan Bernstein is a Bloomberg Opinion columnist covering politics and policy. He taught political science at the University of Texas at San Antonio and DePauw University and wrote A Plain Blog About Politics.
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