Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Nov 27;18(11):e0294507.
doi: 10.1371/journal.pone.0294507. eCollection 2023.

Does the Video Assistant Referee (VAR) mitigate referee bias on professional football?

Thadeu Gasparetto  1 , Kirill Loktionov  2
Affiliations

Does the Video Assistant Referee (VAR) mitigate referee bias on professional football?

Thadeu Gasparetto et al. PLoS One. .

Abstract

The purpose of the paper is to check whether the introduction of the VAR system mitigated the referee bias against away teams. The dataset comprises 2279 matches played in the first tier of the Brazilian League from 2016 to 2021. We analyze 6 seasons of the first tier of the Brazilian domestic football league- 3 seasons before and 3 seasons after the introduction of the VAR technology. Potential bias is viewed through the lens of yellow cards, red cards and number of penalties awarded for both home and away clubs. A paired t-test is used to reveal potential statistical differences between pre-VAR and post-VAR periods, followed by Ordinary Least Squares regressions to inspect whether certain referee' categories have changed their behavior after the implementation of this technology. Our empirical findings offer evidence that the referee bias is diminished, but still present.

PubMed Disclaimer

Conflict of interest statement

The authors have declared that no competing interests exist.

References

    1. de Dios Crespo J. The Contribution of VARs to Fairness in Sport. In: Armenteros M, Benitez AJ, Betancor M, editors. The use of video technologies in refereeing football and other sports Routledge. 2019. pp 23–36.
    1. Tovar J. On Fairness, Justice, and VAR: Russia 2018 and France 2019 World Cups in a Historical Perspective. 1st ed. Springer Nature; 2021.
    1. Chen R, Davidson NP. English Premier League manager perceptions of video assistant referee (VAR) decisions during the 2019–2020 season. Soccer Soc. 2022; 23(1): 44–55.
    1. Dawson P, Dobson S, Goddard J, Wilson J. Are football referees really biased and inconsistent? Evidence on the incidence of disciplinary sanction in the English Premier League. J R Stat Soc Ser A Stat Soc. 2007; 170(1):231–250.
    1. Dawson P, Dobson S. The influence of social pressure and nationality on individual decisions: evidence from the behavior of referees. J Econ Psychol. 2010; 3:181–191