The introduction of the Video Assistant Referee supports the fairness of the game – An analysis of the home advantage in the German Bundesliga

https://doi.org/10.1016/j.psychsport.2023.102386Get rights and content

Highlights

  • VAR improves the fairness of the game.

  • VAR reduces the home advantage.

  • The VAR effect remains significant without the seasons effected by Covid-19.

Abstract

The introduction of the video assistant referee (VAR) was a landmark in soccer history, yet it is not empirically examined whether the technology contributes to the most supreme value of the game: fair play. Because referees are said to be one driving cause of the home advantage (HA), the aim of this study was to examine whether the HA changed in the German Bundesliga since the implementation of the VAR in the season 2017/18. We examined a total of 2448 games during the four seasons before and after the implementation of the VAR with regards to the game outcomes (i.e., goals and points) as well as indicators of referee bias (i.e., fouls, yellow cards, 2nd yellow cards, red cards, and penalty kicks) for both the home and the away teams. Findings indicate that the VAR influences game outcomes to a fairer degree. Specifically, (i) we found statistical evidence for the HA before, but not after the implementation of the VAR. However, (ii) these results need to be interpreted with caution because direct assessments of the change induced by the introduction of the VAR are not statistically significant. Finally, (iii) with the implementation of the VAR, fewer fouls were committed by both the home and the away team.

Section snippets

Purpose of the present study

The aim of this study is to examine if the introduction of the VAR changed the decision-making of the referee in the German Bundesliga. Our present paper builds on the latest studies suggesting that the VAR impacts referees’ decisions (e.g., Han et al., 2020; Holder et al., 2021; Lago-Peñas et al., 2021) by providing a larger dataset over several seasons from one specific league. Specifically, our study added the analysis of 2448 games to the previously analysed 3984 games (n = 480, Han et al.,

Data

We mainly retrieved our data from the website football-data.co.uk (https://www.football-data.co.uk), added penalty kicks from transfermarkt.de (https://www.transfermarkt.de) and separated the 2nd yellow cards from the direct red cards, which gives us the opportunity to trace the difference in direct red cards to the implementation of the VAR. Our constructed dataset included all games in the German Bundesliga four seasons before (2013/14–2016/17) and four seasons after (2017/18–2020/21) the

Results

Descriptive statistics of performance and disciplinary sanctions for the home and the away team in the eight seasons from 2013/14 to 2020/21 are presented in Table 1, Table 2.

The t-tests comparing the game outcomes and the referee bias for the home and the away team can be found in Table 3 to Table 5. Table 3 shows that the number of goals scored (t(1223) = 7.00, p < .001, d = 0.20), points (t(1223) = 7.25, p < .001, d = 0.21), and yellow cards (t(1223) = −6.72, p < .001, d = 0.30) indicate the

Discussion

The VAR was introduced to help make soccer a fairer sport. Previous research has pointed out that the referees may favor the home teams by awarding proportionally fewer fouls, yellow cards, and red cards to them (Boyko et al., 2007; Downward & Jones, 2007; Nevill et al., 2002). This referee bias is one of the main driving forces behind the home advantage. However, if the VAR indeed helps to overcome this bias, the home advantage may decline accordingly. The current study provides new

Declaration of competing interest

None.

References (44)

  • R.H. Boyko et al.

    Referee bias contributes to home advantage in English Premiership football

    Journal of Sports Sciences

    (2007)
  • B. Buraimo et al.

    The 12th man?: Refereeing bias in English and German soccer

    Journal of the Royal Statistical Society: Series A

    (2010)
  • J. Cohen

    Statistical power analysis for the behavioral sciences

    (2013)
  • Fußball-regeln 2021/2022

    (2021)
  • T. Dohmen et al.

    Referee bias

    Journal of Economic Surveys

    (2016)
  • P. Downward et al.

    Effects of crowd size on referee decisions: Analysis of the FA Cup

    Journal of Sports Sciences

    (2007)
  • Laws of the game

    (2019)
  • K. Fischer et al.

    Does crowd support drive the home advantage in professional football? Evidence from German ghost games during the COVID-19 pandemic

    Journal of Sports Economics

    (2021)
  • L. Garicano et al.

    Favoritism under social pressure

    The Review of Economics and Statistics

    (2005)
  • M.A. Gómez-Ruano et al.

    The home advantage phenomenon in sport: History and development

  • B. Han et al.

    The influence of the video assistant referee on the Chinese Super League

    International Journal of Sports Science & Coaching

    (2020)
  • W. Helsen et al.

    Errors in judging “offside” in association football: Test of the optical error versus the perceptual flash-lag hypothesis

    Journal of Sports Sciences

    (2006)
  • View full text