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!”
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.
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.
