Nate Silver Changes His Forecasting Model

Nate Silver: “The changes we made to our pollster ratings earlier this year — namely, no longer privileging live-caller telephone polls — will have some knock-on effects on our models, since our models use our pollster ratings to determine how much weight to assign to polls from different firms.”

“And as I mentioned, while our models already assume that the errors between different races are correlated, those correlations may be even higher in an era of greater partisanship, so we’ll want to look at that, too.”

FiveThirtyEight’s “deluxe” model fared particularly poorly in toss-up congressional races in 2020, only correctly forecasting 37% of them.