Survey Statistics: Big Changes in the Times/Siena Poll

Yesterday Nate Cohn wrote about The Big Changes Coming to the Times/Siena Poll, with more details in their poll of Maine. Say we want to estimate average Platner support in Maine’s likely electorate, E(Y). But we only have survey respondents, R = 1. The NYT uses survey weights to weight respondents, E(YW | R = 1). In contrast, some pollsters use MRP, fitting a Multilevel Regression model for Platner support, then applying it to the population, E(E_model(Y | X, R = 1)). Nate discusses 2 Big Changes to how they construct the weights W. (The polar bear has not yet hiked in ME, but he is training for it. This above is in TN.) Big Change 1: Support score A few weeks ago we saw the NYT started weighting on “synthetic 2024 vote”, which is recalled 2024 vote that is validated with the voter file and imputed if needed. Now they’re also weighting on support score = E(2024 vote | other X variables). Nate explains the motivation: While a poll can’t weight on dozens of variables, the support score…