We assess how the PollyVote and its components performed in this election compared to the previous six (1992 to 2012). While always predicting that Hillary Clinton would win the popular vote, across the 100 days leading to the election on average the PollyVote overshot the mark by 1.9 percentage...

We summarize the literature on the effectiveness of combining forecasts by assessing the conditions under which combining is most valuable. Using data on the six U.S. Presidential elections from 1992 through 2012, we then report the reduction in error obtained by averaging forecasts within and...