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The PollyVote project uses the high-profile application of predicting U.S. presidential election results to demonstrate advances in forecasting research. The project is run by political science professors and forecasting experts, one of which is J. Scott Armstrong. All procedures, data, and results are fully disclosed and freely available online. The project started in March 2004 to demonstrate the benefits of combining forecasts. In averaging forecasts within and across different forecasting methods, the combined PollyVote forecast provided highly accurate predictions of the two-party popular vote shares for the last three U.S. presidential elections. == History == The PollyVote was created in March 2004 by marketing and forecasting expert J. Scott Armstrong and political science professors (Alfred Cuzán ) and (Randall Jones ). The goal at that time was to apply the combination principle in forecasting to predict President Bush's share of the two-party popular vote (omitting minor candidates) in the 2004 presidential election. Until Election Day in November of the same year, the researchers collected data from 268 polls, 10 quantitative models, and 246 daily market prices from the Iowa Electronic Markets vote-share market. In each of the last three months prior to the election, they also administered a survey with a panel of 17 experts on US politics, asking them for their predictions. The forecasts were first combined within each component method by averaging recent polls, the IEM prediction market forecasts from the previous week, and averaging the predictions of the quantitative models. Then, the researchers averaged the forecasts across the four component methods. The resulting forecast was named the PollyVote. From March to November, the forecasts were initially updated weekly, and then, twice a week. The forecasts were published at the Political Forecasting Special Interest Group at forprin.com. In 2007, (Andreas Graefe ) joined the PollyVote team and helped to launch the PollyVote.com website prior to the 2008 U.S. presidential election. For predicting the 2008 election, the general structure of the PollyVote remained unchanged; the PollyVote combined forecasts within and across the same four component methods as in 2004. However, some changes were made at the level of the component methods. Instead of averaging recent polls themselves, the PollyVote team used the RCP poll average by RealClearPolitics as the polls component. In addition, the advantage of the leading candidate was discounted (or damped) using the approach suggested by Jim Campbell. The first PollyVote forecast for the 2008 election was published in August 2007, 14 months prior to Election Day, and was updated daily. For forecasting the 2012 election, a fifth component called "index models" was added to the PollyVote. This component captured information from quantitative models that use a different method and rely on different information than the traditional political economy models. In particular, the index models capture information about the campaign, such as the candidates' perceived issue-handling competence, their leadership skills, their biographies or the influence of other factors such as whether the incumbent government faced some scandal. The first forecast for the 2012 election was published on January 1, 2011, almost two years prior to Election Day. As in 2008, the forecasts were updated daily, or whenever new information became available.〔 In 2013, the PollyVote was launched in Germany to predict the German federal election of the same year. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「PollyVote」の詳細全文を読む スポンサード リンク
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