What will the difference be between the national popular vote, and Nate Silver's polling average, for the 2024 US Presidential Election - in other words, what is the polling miss for the year?
The miss will be expressed as the poll bias: for example, if the national popular vote is D+2, and the polling average is D+5, this will resolve to a D+3 miss.
Given the long tail of mail in and corrected ballots, I intend on resolving this one month after the election - though if there is a major legal fight over ballots I might resolve it at the time of inauguration, or if the answer is not close to changing brackets (e.g. <0.1% of votes expected to change) I may create a poll to resolve the market early.
The polling average used will be the final pre-election average found here: https://www.natesilver.net/p/nate-silver-2024-president-election-polls-model
The national popular vote will be aggregated from various state Secretary of State releases, and is usually identical between all major data providers. (A single source could be provided later if this is a sticking point for anyone, but I haven't seen substantial disagreements.)
1,000
3.00Nate Silver's final election model has been run, and the national vote polling average says D+1, which is what this question will resolve against.
One interesting note is that state polls are better for Harris than the national polls are. Nate's model, not the calculated polling average, thinks the bottom up analysis would put Harris at D+2.1!
““Some people will start a poll, they’ll tell you who they’re going to vote for and then they say, ‘I’m done. I don’t want to talk to you anymore. Goodbye,’” Don Levy, director of the Siena College Research Institute, which helps conduct polls for the New York Times, told CNBC. “In 2020 and 2022, we didn’t count those people.”
But this time around, Levy says they are counting the “drop-offs.”
They found that if they had counted those impatient respondents in 2020 and 2022, their poll results would have moved “about a point and a quarter in the Trump direction,” Levy said, eliminating roughly 40% of their error.”
Nate Silver weighs in directly on the polling miss question: https://www.natesilver.net/p/sbsq-12-will-the-polls-lowball-trump
I tried to do a quick search if one already existed before making this market, but my initial pass missed a similar but not identical market (using RCP’s polling average, which I am not a fan of, and different brackets): https://manifold.markets/Weezing/what-will-be-the-polling-error-in-2