A comparison of forecasting methods: fundamentals, polling, prediction markets, and experts

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Deepak Pathak
David Rothschild
Miroslav Dudik

Abstract

We compare Oscar forecasts derived from four data types (fundamentals, polling, prediction markets, and domain experts) across three attributes (accuracy, timeliness and cost effectiveness). Fundamentals-based forecasts are relatively expensive to construct, an attribute the academic literature frequently ignores, and update slowly over time, constraining their accuracy. However, fundamentals provide valuable insights into the relationship between key indicators for nominated movies and their chances of victory. For instance, we find that the performance in other awards shows is highly predictive of the Oscar victory whereas box office results are not. Polling- based forecasts have the potential to be both accurate and timely. Timeliness requires incentives for frequent responses by high-information users. Accuracy is achieved by a proper transformation of raw polls. Prediction market prices are accurate forecasts, but can be further improved by simple transformations of raw prices, yielding the most accurate forecasts in our study. Expert forecasts exhibit some characteristics of fundamental models, but are generally not comparatively accurate or timely. This study is unique in both comparing and aggregating four traditional data sources, and considering critical attributes beyond accuracy. We believe that the results of this study generalize to many other domains.

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References

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