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Does confirmation bias exist in judged events at the Olympic Games?

  • Christiana Hilmer EMAIL logo and Michael John Hilmer


Examining data for the 10 Olympic Games contested this century, we ask whether confirmation bias exists in judged events. We theorize that if such bias is present, then competitors in judged events should perform closer to predicted than competitors in non-judged events. Among a sample of over 5100 predicted medalists from the 10 Games, we find that, all else equal, the differences between ex-ante conventional wisdom and ex-post observed outcome are larger for competitors in timed events than for competitors in judged events. These results suggest that confirmation bias does potentially exist for judged events at the Olympic Games.

Corresponding author: Christiana Hilmer, San Diego State University, Department of Economics, 5500 Campanile Drive, San Diego, California, USA, 92182-4485, E-mail:

  1. Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: None declared.

  3. Conflict of interest statement: The authors declare no conflicts of interest regarding this article.


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Received: 2019-05-21
Accepted: 2020-10-06
Published Online: 2020-11-02
Published in Print: 2021-01-26

© 2020 Walter de Gruyter GmbH, Berlin/Boston

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