Replication data for: Accuracy of combined forecasts for the 2012 Presidential Election: The PollyVote

We review the performance of the PollyVote, which combined forecasts from polls, prediction markets, experts’ judgment, political economy models, and index models to forecast the two-party popular vote in the 2012 U.S. Presidential Election. Throughout the election year the PollyVote provided highly accurate forecasts, outperforming each of its component methods, as well as the forecasts from FiveThirtyEight.com. Gains in accuracy were particularly large early in the campaign, when uncertainty about the election outcome is typically high. The results confirm prior research showing that combining is one of the most effective approaches to generating accurate forecasts.

我们对PollyVote的表现进行了综述，该模型整合了民调、预测市场、专家判断、政治经济学模型以及指数模型的预测结果，用于预测2012年美国总统选举的两党普选票得票情况。在整个竞选年度中，PollyVote始终提供高精度的预测结果，其表现优于所有组成方法，同时也超越了FiveThirtyEight.com发布的预测结果。预测精度的提升在竞选初期尤为显著，而此时选举结果的不确定性通常处于较高水平。本研究结果验证了此前的相关研究结论，即组合预测是生成高精度预测结果的最有效方法之一。