Prior research offers a mixed view of the value of expert surveys for long-term election forecasts. On the positive side, experts have more information about the candidates and issues than voters do. On the negative side, experts all have access to the same information. Based on prior literature...

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 review the performance of the PollyVote, which combined forecasts from polls, prediction markets, experts’ judgment, political economy models, and index models to predict the two-party popular vote in the 2012 US presidential election. Throughout the election year the PollyVote provided...

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...

At PoliticalForecasting.com, better known as the Pollyvote, the authors combine forecasts from four sources: election polls, a panel of American political experts, the Iowa Electronic Market, and quantitative models. The day before the election, Polly predicted that the Republican ticket’s...

In the PollyVote, we evaluated the combination principle to forecast the five U.S. presidential elections between 1992 and 2008. We combined forecasts from three or four different component methods: trial heat polls, the Iowa Electronic Markets (IEM), quantitative models and, in the 2004 and...

Scott Armstrong and Alfred Cuzan describe Allan Lichtman's Keys Model as an example of an index method of forecasting, which assigns ratings of favorable, unfavorable, or indeterminate to influencing variables. They describe how index methods have been applied in other decision-making contexts,...