Nate Silver @NateSilver538
@gelliottmorris @DanRosenheck @Nate_Cohn @collprof @Michael_Cobb68 For example, it could be that polling gets more accurate over the course of say 1948-2012 but is now becoming less accurate again. That's also a plausible story that fits the data well but it has pretty different implications for 2020. — PolitiTweet.org