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Oh.
Wait, are you telling me that response rate is so warped as to effect samples? Just how lopsided is it, Mr. Cohn?
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RESPONSE BIAS IS DISTORTING POLLING, PRIORS VINDICATED
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Getting real close to an “oh my god he admit it” moment.
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Me, not a stats guy, but also not stats illiterate: “surely these models have an adequate mechanism for dealing with something as obvious as ‘old republicans are picking up the phone, while others aren’t, really.” The Nates: “nope!”
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It's always been CW that response rates may be responsible for temporary polling bumps. That they are responsible for longer term polling results, pollsters may not want to admit.
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OMG. Cohn has changed from a few months ago
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That’s something the individual pollsters try to do before putting out the poll results, by reducing the weight of responses from groups more likely to answer. But that can only do so much, if the response issue is so bad that there’s no good data to weight.
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It’s part of why it’s silly to get too granular about the Nates’ approach of combining all the polls into a meta model. They’re combining weighted results of different polls with different methodologies and weights. Nice for a quick overview if you don’t want to dig into methodologies, that’s all.
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Makes sense. Joking aside, I’m glad the article centers the issue. It’s good information and I’m glad they acknowledge it!
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I'm not a polling or stats expert, but my understanding is that the way they would typically correct for a response bias is by projecting the results using models of prior electorates. The real problems is that we're *also* experiencing a major political realignment
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So, like, the prior electorates don't map cleanly onto the current electorates. So, one of the main strategies for resolving these kinds of response rate issues is severely impacted by the *other* major trend affecting pollsters
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With how spammy phones have gotten, I’m afraid we’ve reached the point where “people who answer unknown number” are not representative of the the voting population
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Totally. My kid, who will vote, looked at me like I had two heads when I suggested they answer the phone. “I never answer the phone when it’s an unknown number” they said. (I was like, suppose it’s a job or something else important? They said they check their phone messages.)
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They correct for this by weighting by recalled Trump vote. The topline results are close to correct, but for anything other than the presidential horserace you'll have too many hardcore Rs and not enough moderate Rs.