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Information markets vs. opinion pools: an empirical comparison

Published:05 June 2005Publication History

ABSTRACT

In this paper, we examine the relative forecast accuracy of information markets versus expert aggregation. We leverage a unique data source of almost 2000 people's subjective probability judgments on 2003 US National Football League games and compare with the "market probabilities" given by two different information markets on exactly the same events. We combine assessments of multiple experts via linear and logarithmic aggregation functions to form pooled predictions. Prices in information markets are used to derive market predictions. Our results show that, at the same time point ahead of the game, information markets provide as accurate predictions as pooled expert assessments. In screening pooled expert predictions, we find that arithmetic average is a robust and efficient pooling function; weighting expert assessments according to their past performance does not improve accuracy of pooled predictions; and logarithmic aggregation functions offer bolder predictions than linear aggregation functions. The results provide insights into the predictive performance of information markets, and the relative merits of selecting among various opinion pooling methods.

References

  1. http://us.newsfutures.comGoogle ScholarGoogle Scholar
  2. http://www.biz.uiowa.edu/iem/Google ScholarGoogle Scholar
  3. http://www.hsx.com/Google ScholarGoogle Scholar
  4. http://www.ideosphere.com/fx/Google ScholarGoogle Scholar
  5. http://www.probabilityfootball.com/Google ScholarGoogle Scholar
  6. http://www.probabilitysports.com/Google ScholarGoogle Scholar
  7. http://www.tradesports.com/Google ScholarGoogle Scholar
  8. A. H. Ashton and R. H. Ashton. Aggregating subjective forecasts: Some empirical results. Management Science, 31:1499--1508, 1985.Google ScholarGoogle ScholarDigital LibraryDigital Library
  9. R. P. Batchelor and P. Dua. Forecaster diversity and the benefits of combining forecasts. Management Science, 41:68--75, 1995. Google ScholarGoogle ScholarDigital LibraryDigital Library
  10. N. Cesa-Bianchi, Y. Freund, D. Haussler, D. P. Helmbold, R. E. Schapire, and M. K. Warmuth. How to use expert advice. Journal of the ACM, 44(3):427--485, 1997. Google ScholarGoogle ScholarDigital LibraryDigital Library
  11. K. Chen, L. Fine, and B. Huberman. Predicting the future. Information System Frontier, 5(1):47--61, 2003. Google ScholarGoogle ScholarDigital LibraryDigital Library
  12. R. T. Clemen and R. L. Winkler. Combining probability distributions from experts in risk analysis. Risk Analysis, 19(2):187--203, 1999.Google ScholarGoogle ScholarCross RefCross Ref
  13. R. M. Cook. Experts in Uncertainty: Opinion and Subjective Probability in Science. Oxford University Press, New York, 1991.Google ScholarGoogle Scholar
  14. A. L. Delbecq, A. H. Van de Ven, and D. H. Gustafson. Group Techniques for Program Planners: A Guide to Nominal Group and Delphi Processes. Scott Foresman and Company, Glenview, IL, 1975.Google ScholarGoogle Scholar
  15. E. F. Fama. Efficient capital market: A review of theory and empirical work. Journal of Finance, 25:383--417, 1970.Google ScholarGoogle ScholarCross RefCross Ref
  16. R. Forsythe and F. Lundholm. Information aggregation in an experimental market. Econometrica, 58:309--47, 1990.Google ScholarGoogle ScholarCross RefCross Ref
  17. R. Forsythe, F. Nelson, G. R. Neumann, and J. Wright. Forecasting elections: A market alternative to polls. In T. R. Palfrey, editor, Contemporary Laboratory Experiments in Political Economy, pages 69--111. University of Michigan Press, Ann Arbor,MI, 1991.Google ScholarGoogle Scholar
  18. R. Forsythe, F. Nelson, G. R. Neumann, and J. Wright. Anatomy of an experimental political stock market. American Economic Review, 82(5):1142--1161, 1992.Google ScholarGoogle Scholar
  19. R. Forsythe, T. A. Rietz, and T. W. Ross. Wishes, expectations, and actions: A survey on price formation in election stock markets. Journal of Economic Behavior and Organization, 39:83--110, 1999.Google ScholarGoogle ScholarCross RefCross Ref
  20. S. French. Group consensus probability distributions: a critical survey. Bayesian Statistics, 2:183--202, 1985.Google ScholarGoogle Scholar
  21. C. Genest. A conflict between two axioms for combining subjective distributions. Journal of the Royal Statistical Society, 46(3):403--405, 1984.Google ScholarGoogle Scholar
  22. C. Genest. Pooling operators with the marginalization property. Canadian Journal of Statistics, 12(2):153--163, 1984.Google ScholarGoogle ScholarCross RefCross Ref
  23. C. Genest, K. J. McConway, and M. J. Schervish. Characterization of externally Bayesian pooling operators. Annals of Statistics, 14(2):487--501, 1986.Google ScholarGoogle ScholarCross RefCross Ref
  24. C. Genest and J. V. Zidek. Combining probability distributions: A critique and an annotated bibliography. Statistical Science, 1(1):114--148, 1986.Google ScholarGoogle ScholarCross RefCross Ref
  25. S. J. Grossman. An introduction to the theory of rational expectations under asymmetric information. Review of Economic Studies, 48(4):541--559, 1981.Google ScholarGoogle ScholarCross RefCross Ref
  26. F. A. Hayek. The use of knowledge in society. American Economic Review, 35(4):519--530, 1945.Google ScholarGoogle Scholar
  27. J. C. Jackwerth and M. Rubinstein. Recovering probability distribution from options prices. Journal of Finance, 51(5):1611--1631, 1996.Google ScholarGoogle ScholarCross RefCross Ref
  28. H. A. Linstone and M. Turoff. The Delphi Method: Techniques and Applications. Addison-Wesley, Reading, MA, 1975.Google ScholarGoogle Scholar
  29. P. A. Morris. Decision analysis expert use. Management Science, 20(9):1233--1241, 1974.Google ScholarGoogle ScholarCross RefCross Ref
  30. P. A. Morris. Combining expert judgments: A bayesian approach. Management Science, 23(7):679--693, 1977.Google ScholarGoogle ScholarDigital LibraryDigital Library
  31. P. A. Morris. An axiomatic approach to expert resolution. Management Science, 29(1):24--32, 1983.Google ScholarGoogle ScholarDigital LibraryDigital Library
  32. E. W. Noreen. Computer-Intensive Methods for Testing Hypotheses: An Introduction. Wiley and Sons, Inc., New York, 1989.Google ScholarGoogle Scholar
  33. D. M. Pennock, S. Lawrence, C. L. Giles, and F. A. Nielsen. The real power of artificial markets. Science, 291:987--988, February 2002.Google ScholarGoogle ScholarCross RefCross Ref
  34. D. M. Pennock, S. Lawrence, F. A. Nielsen, and C. L. Giles. Extracting collective probabilistic forecasts from web games. In Proceedings of the 7th ACM SIGKDD International Conference on Knowledge Discovery and Data Mining, pages 174--183, San Francisco, CA, 2001. Google ScholarGoogle ScholarDigital LibraryDigital Library
  35. C. Plott and S. Sunder. Rational expectations and the aggregation of diverse information in laboratory security markets. Econometrica, 56:1085--118, 1988.Google ScholarGoogle ScholarCross RefCross Ref
  36. E. Servan-Schreiber, J. Wolfers, D. M. Pennock, and B. Galebach. Prediction markets: Does money matter? Electronic Markets, 14(3):243--251, 2004.Google ScholarGoogle ScholarCross RefCross Ref
  37. M. Spann and B. Skiera. Internet-based virtual stock markets for business forecasting. Management Science, 49(10):1310--1326, 2003. Google ScholarGoogle ScholarDigital LibraryDigital Library
  38. M. West. Bayesian aggregation. Journal of the Royal Statistical Society. Series A. General, 147(4):600--607, 1984.Google ScholarGoogle ScholarCross RefCross Ref
  39. R. L. Winkler. The consensus of subjective probability distributions. Management Science, 15(2):B61--B75, 1968.Google ScholarGoogle ScholarDigital LibraryDigital Library
  40. J. Wolfers and E. Zitzewitz. Prediction markets. Journal of Economic Perspectives, 18(2):107--126, 2004.Google ScholarGoogle ScholarCross RefCross Ref

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    • Published in

      cover image ACM Conferences
      EC '05: Proceedings of the 6th ACM conference on Electronic commerce
      June 2005
      302 pages
      ISBN:1595930493
      DOI:10.1145/1064009

      Copyright © 2005 ACM

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      Publication History

      • Published: 5 June 2005

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