Nate Silver @NateSilver538
It's more of a sliding scale than a fixed time horizon, where our algorithm is trying to manage a trade-off between quality and recency. But you also need to account for house effects; the polls in the RCP average in PA are a really friendly set for Trump. https://t.co/wxRaq7bDjI — PolitiTweet.org
Frank Luntz @FrankLuntz
@NateSilver538 How far back is your time horizon? Do more recent polls get weighted higher in such an average?