[jbarciauskas]

This is lacks a strong causal analysis. We still don't understand why polls are consistently undershooting Trump support. Given the performance of polls in 2018, it seems highly correlated to Trump's presence on the ballot, and unclear if it will recur in a future presidential election. Ascribing better analysis to markets than polls requires us to ask "how?", and there isn't a clear mechanism.

[pgwhalen]

> This is lacks a strong causal analysis.

FWIW I am also unconvinced by the article's thesis that prediction markets "beat" polls. But I'm not sure I agree with your premise that we need to ascribe causality if markets beat polls. The "point" of markets is that they work in mysterious ways: the combination of financial incentives and the wisdom of the crowd coalesce to price things correctly. You might be able to point out why a specific market participant has a specific opinion and makes a specific bet, but doing so for the entire market is a fool's errand.

[rootusrootus]

In aggregate the polls were off by an entirely normal amount. What you can't do is predict how they will fair in a future election, because the pollsters themselves change strategy every time. It's as likely to be off in the other direction come 2024.

[JamesBarney]

Most of the admittedly very early analysis I've read is basically it's low trust voters.

Low trust voters are hard to poll because they don't trust pollsters, they don't pick up their phone for strangers.

6 years ago this didn't matter because they were as likely to be Republican as Democratic. But that changed with Trump who appeals to these types of voters.

Then this election democrats suddenly increased their civic engagement which lead to them being much more likely to talk to pollsters. Skewing the results.

[danhor]

One other popular theory is having to do with democrats staying at home post-COVID and republicans ... not doing so. Nate Cohn seems to think it's pretty plausible https://www.nytimes.com/2020/11/10/upshot/polls-what-went-wr....

[wutbrodo]

I know these are young comments, but I'm fascinated by the downvote patterns I'm seeing here. I didn't think of anything in your comment as remotely controversial; I thought it was the consensus best-guess of why polls are underperforming, as described by very mainstream sources like the NYT.

[ghayes]

Yeah I’m equally confused on the downvotes for completely reasonable posts here.

[dragonwriter]

That would explain change over time, but it has problem with why the problem disappears in between 2016 and 2018 and returns in 2020, so even if it is accurate, it seems to be incomplete.

[JamesBarney]

I think the explanation is basically they corrected for the first problem that happened in 2016 in 2018, but the second problem didn't appear until 2020.

[ECA_stax]

lack of trust of polling. also there are risks of outing oneself as a Trump supporter in blue areas outweigh the risks of outing oneself as a Biden supporter in red areas.

[Longwelwind]

538 has a rundown on why the Shy Trump Voters theory doesn't seem to exist in practice: https://fivethirtyeight.com/features/trump-supporters-arent-...