Combining Forecasts: An Application to Elections

  title={Combining Forecasts: An Application to Elections},
  author={Andreas Graefe and J. Scott Armstrong and Randall J. Jones and Alfred G. Cuz{\'a}n},
  journal={Forecasting Models eJournal},

German Election Forecasting: Comparing and Combining Methods for 2013

The present study reviews the accuracy of four methods for forecasting the 2013 German election: polls; prediction markets; expert judgement; and quantitative models. On average, across the two

Accuracy of Combined Forecasts for the 2012 Presidential Election: The PollyVote

ABSTRACT 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

Embrace the Differences: Revisiting the Pollyvote Method of Combining Forecasts for U.S. Presidential Elections (2004 to 2020)

  • A. Graefe
  • Environmental Science
    SSRN Electronic Journal
  • 2021
While combining forecasts is well-known to reduce error, the question of how to best combine forecasts remains. Prior research suggests that combining is most beneficial when relying on diverse

Accuracy gains of adding vote expectation surveys to a combined forecast of US presidential election outcomes

In averaging forecasts within and across four-component methods (i.e. polls, prediction markets, expert judgment and quantitative models), the combined PollyVote provided highly accurate predictions

Improving Causal Models for Election Forecasting: Further Evidence on the Golden Rule of Forecasting

The Golden Rule of Forecasting counsels forecasters to be conservative when making forecasts. We tested the value of three of the four Golden Rule guidelines that apply to causal models: modify

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This study analyzes the relative accuracy of experts, polls, and the so-called ‘fundamentals’ in predicting the popular vote in the four U.S. presidential elections from 2004 to 2016. Although

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Do Econometric Models Provide More Accurate Forecasts When They are More Conservative? A Test of Political Economy Models for Forecasting Elections

The assumptions of multiple regression analysis are not met in many practical forecasting situations and, as a result, regression models are insufficiently conservative. We tested the effect on



Combining Forecasts

To improve forecasting accuracy, combine forecasts derived from methods that differ substantially and draw from different sources of information. When feasible, use five or more methods. Use formal

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Combined Forecasts of the 2008 Election: The Pollyvote

At, 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

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We used the take-the-best heuristic to develop a model to forecast the popular two party vote shares in U.S. presidential elections. The model draws upon information about how voters expect the

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The expected error variance of a combined forecast is necessarily lower than that of an individual forecast, but in practice there may be considerable variation around these expected values. This

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Combination forecasts of output growth in a seven-country data set

This paper uses forecast combination methods to forecast output growth in a seven-country quarterly economic data set covering 1959-1999, with up to 73 predictors per country. Although the forecasts

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Polls and Votes

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