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.
Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: None declared.
Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
Andrews, R. J., T. D. Logan, and M. J. Sinkey (2012). Identifying Confirmatory Bias in the Field: Evidence from a Poll of Experts. NBER Working Papers, 18064, https://doi.org/10.3386/w18064.Search in Google Scholar
Armour, N. 2018. No One Expected Ester Ledicka to Win the Super-G. Not Even Her. USA Today. https://www.usatoday.com/story/sports/winter-olympics-2018/2018/02/17/no-one-expected-ester-ledecka-win-super-g/347750002/ (accessed February 17, 2018).Search in Google Scholar
Bialik, C. 2012. “Removing Judges’ Bias is Olympic-Size Challenge.” The Wall Street Journal. https://www.wsj.com/articles/SB10000872396390443477104577551253521597214 (accessed July 27, 2012).Search in Google Scholar
Crouse, K. 2008. Phelps Wins 7th Gold with 0.01 to Spare. https://www.nytimes.com/2008/08/16/sports/olympics/16swim.html (accessed August 15 2008).Search in Google Scholar
Cloyd, C., and B. Spilker. 2000. “Confirmation Bias in Tax Information Search: A Comparison of Law Students and Accounting Students.” Journal of American Taxation Association: Fall 22 (2): 60–71, https://doi.org/10.2308/jata.2000.22.2.60.Search in Google Scholar
Duong, C., G. Pescetto, and D. Santamaria. 2014. “How Value-Glamour Investors Use Financial Information: UK Evidence of Investors’ Confirmation Bias.” The European Journal of Finance 20 (6): 524–49, https://doi.org/10.1080/1351847x.2012.722117.Search in Google Scholar
Forbes. 2010. The Man Who Predicts the Medals. https://www.forbes.com/2010/01/19/olympic-medal-predictions-business-sports-medals.html#2129f662b1b3 (accessed January 19, 2010).Search in Google Scholar
Goldenberg, D. 2006. Grading Olympic Predictions. Also available at http://www.gelfmagazine.com/archives/grading_olympic_predictions.php.Search in Google Scholar
Knobloch-Westerwick, S., B. Johnson, and A. Westerwick. 2015. “Confirmation Bias in Online Searches: Impacts of Selective Exposure before an Election on Political Attitude Strength and Shifts.” Journal of Computer-Mediated Communication 20 (2): 171–87, https://doi.org/10.1111/jcc4.12105.Search in Google Scholar
McCarthy, N., and D. Collins. 2014. ““Initial Identification and Selection Bias versus the Eventual Confirmation of Talent” Evidence for the Benefits of a Rocky Road.” Journal of Sports Science 32 (17): 1604–10, https://doi.org/10.1080/02640414.2014.908322.Search in Google Scholar PubMed
Ma, J. 2014. The Betting Mistakes we all Make. ESPN. Also available at http://www.espn.com/chalk/story/_/id/11863567/betting-five-biggest-cognitive-biases-impair-sports-bettors-most.Search in Google Scholar
McNerney, S. 2011. “Confirmation Bias and Art.” Scientific American. Also available at https://blogs.scientificamerican.com/guest-blog/confirmation-bias-and-art/.Search in Google Scholar
Mendel, R., E. Traut-Mattausch, and E. Jones. 2011. “Confirmation Bias: Why Psychiatrists Stick to Wrong Preliminary Diagnoses.” Psychological Medicine 41 (12): 2651–9, https://doi.org/10.1017/s0033291711000808.Search in Google Scholar PubMed
Park, J., P. Konana, B. Gu, A. Kumar, and R. Raghunathan. 2013. “Information Bias in Virtual Communities: Evidence from Stock Message Board.” Home Information Systems Research 24 (4): 1050–67, doi:https://doi.org/10.1287/isre.2013.0492.Search in Google Scholar
Pera, M. 2015. “Sharing Behaviour of Bitcoin Investors – Evidence of Confirmation Bias?” https://aaltodoc.aalto.fi/handle/123456789/21382. Master’s Thesis, Rahoituksen Iaitos, Department of Finance.Search in Google Scholar
Pilon, M., A. Lehren, S. Gosk, E. Siegel, and K. Abou-Sabe. 2018. Think Olympic Figure Skating Judges are Biased? The Data Says they Might be. https://www.nbcnews.com/storyline/winter-olympics-2018/think-olympic-figure-skating-judges-are-biased-data-says-they-n844886 (accessed February 6, 2018).Search in Google Scholar
Pinnacle.com. 2013. Confirmation Bias. Also available at https://www.pinnacle.com/en/betting-articles/Betting-Psychology/how-confirmation-bias-affects-your-betting/79425XBAQM6NPE72.Search in Google Scholar
Plous, S. 1993. McGraw-Hill Series in Social Psychology. The Psychology of Judgment and Decision Making. New York, NY, England: Mcgraw-Hill Book Company.Search in Google Scholar
Rodenberg, R. 2011. “Perception? Reality: Analyzing Specific Allegations of NBA Referee Bias.” Journal of Quantitative Analysis in Sports 7 (2): 8–8, doi:https://doi.org/10.2202/1559-0410.1326.Search in Google Scholar
Ruzicka, L. 2018. 5 Ways Losing Sports Bettors Make Confirmation Bias Mistakes. ESPN. https://www.livebetting.net/blog/5-ways-losing-sports-bettors-make-confirmation-bias-mistakes/.Search in Google Scholar
Shamsian, J. 2016. Here’s How Olympic Judges Get Chosen. https://www.insider.com/how-are-olympic-judges-selected-2016-8 (accessed August 10, 2016).Search in Google Scholar
Shipka, T. 2012. Michael Shermer, Skeptic. Also available at https://wysu.org/content/commentary/michael-shermer-skeptic.Search in Google Scholar
Van den Berge, K., and S. Marmede. 2013. “Cognitive Diagnostic Error in Internal Medicine.” European Journal of Internal Medicine 24 (6): 525–9, https://doi.org/10.1016/j.ejim.2013.03.006.Search in Google Scholar PubMed
Wason, P. C. 1960. “On the Failure to Eliminate Hypotheses in a Conceptual Task.” Quarterly Journal of Experimental Psychology 12 (3): 129–40, https://doi.org/10.1080/17470216008416717.Search in Google Scholar
© 2020 Walter de Gruyter GmbH, Berlin/Boston