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Swing-state fails: Predicting them in June is tricky

Three tips for poll obsessors (like me), in a presidential election year, followed by a few insights from Nate Silver’s The first two below are old and obvious, so feel free to skip to No. 3, which is not.

    1. Polls are not predictions. Everyone knows this, but most of us ignore it most of the time. They are fuzzy-focused snapshots of a moment that has already passed by the time you read them. Fuzzy refers to the fact that, given the margins for sampling error (which we tend to ignore when we look at polls) means that a poll showing candidate X ahead by plus or minus three points means he might be ahead by six or the race might be tied. And by the time you read the poll, the situation may have changed. This is a pretty good argument for paying less attention to them, but I can’t help myself.
    2. Obviously, in a presidential election, national poll numbers (in addition to be being fuzzy and out of date) are almost irrelevant; it’s the swing states that matter.
    3. We don’t know which states those are. This is less obvious point, and the analysis is pretty surprising. recently looked back at the last four presidential elections, and focused on the states that the estimable Cook Political Report had identified as the key swing states five months ahead of the election (which is where are now). Then they looked at the final election results to see if those “swing” states turned out to be very close in the actual election. Cook’s list turned out to be “wrong,” much of the time, not in predicting which way the swing states would swing, but in predicting which states would be close enough on Election Day to merit the status of “swing” states. It’s a fairly impressive bit of research. In each of the last three presidential elections, Cook’s list of swing states in June turned out to contain more states that didn’t end up being close in the end than states that were.

Cook’s June swing-state list also, in three of the last four presidential elections, left off several states that turned out to be much closer. The really big example of how wrong these June lists turned out to be was 2016, when, of four states identified as the key swing states, two of them turned out to be close, and two didn’t.

But – and here’s the big deal – NINE other states that weren’t on the June swing-state list turned out to be quite close (including our own beloved Minnesota). This is not about the folks at Cook being dumb. They’re not. They’re smart. It’s about the unknowability of November from the standpoint of June.

Here’s the full piece with the right, wrong, and missing calls for the past four elections.

I absolutely agree with the point of the 538 piece. It’s not that the Cook team isn’t smart; it’s that the future is unknowable, which is really annoying. (And I know, too, that I will continue to notice when the list of predicted swing states is adjusted. I only hope this analysis will help me keep my shirt on when that occurs.)

Comments (5)

  1. Submitted by Roy Everson on 06/19/2020 - 01:47 am.

    There are swing states that have swung but no longer swing, swing states that continue to swing, and states that never swing but are on the verge of first-time swinging with other consenting swinging states.. When we talk about people this way we’re being nosy, but with states we’re talking politics.

  2. Submitted by BK Anderson on 06/19/2020 - 07:19 am.

    The previously solid Blue states that went to Trump in 2016 are (by definition) going to be “swing states” this time around, and Trump is certainly going to be spending time in the failed states of PA, MI and WI once again. The denizens of those states can never erase the fact that they were the states that saddled the nation with one of the worst two presidents in history and (probably) permanently wrecked the country. Hell, they may do it again! It’s not like there’s any idea of repentance by those white Trump supporters.

    But yes, this time around there are also going to be a dozen (previously solid Red) “swing states”, simply because the odious Trump is hanging on by his fingernails in places like AZ, NC and IA. For goodness sake, if the Repubs in GA,TX, OH and FL hadn’t thoroughly gamed and rigged those states to suppress Dem voters and make a Dem victory impossible, THOSE states– basically the backbone of the “conservative” movement–would be “swing states” in 2020!

    Trump has definitely “altered the playing field” as they say, but it’s not clear it’s very much in his favor this time around.

    • Submitted by Brian Simon on 06/19/2020 - 12:46 pm.

      “The denizens of those states can never erase the fact that they were the states that saddled the nation with one of the worst two presidents in history and (probably) permanently wrecked the country. Hell, they may do it again!”

      I see a lot of parallels between that observation & criticisms of protests that get violent & destructive.

      What did Janis say? “When you got nothin, you got nothin to lose.”

      People who this society has passed by are willing to “burn it down” to foment change, because nothing else has worked. Trump found a way to tap into that energy among a limited demographic. I’d like to think the right Dem could’ve done it in a more widespread way.

      • Submitted by Paul Brandon on 06/19/2020 - 02:11 pm.

        Kristofferson’s lyric:
        Freedom’s just another word for nuthin left to lose,
        Nuthin aint worth nuthin but it’s free…

        That what you mean?

  3. Submitted by Brian Simon on 06/19/2020 - 09:05 am.

    My takeaway from 2016 was less about specific states & more about how demographic groups effect outcomes across states. Point being: yes, nationwide polling is a blunt instrument by which to gauge results. But when you look at white men without college degrees, you see how they move multiple states at once. It was shifts in this group that flipped WI, MI, PA & OH. Point being, making shifts in demograpgic groups can turn the tide in large swaths of the country. It’s less about pandering to WI voters than about tapping into the frustrations of out-of-work blue collar workers across the midwest.

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