Video Assistant Referee and Home Advantage: The Case of Brazilian Soccer Championship

Árbitro assistente de vídeo e vantagem em casa: o caso do campeonato brasileiro de futebol

Abstract

Home-field advantage is a phenomenon well-recognized both by fans and literature. This study analyses the impact of the video assistant referees (VAR) at home advantage. It tests if the VAR – a referee that can rectify the decision of the field referee in some moments – decreased the referee bias. The study modeled the performance of 16 teams playing the Brazilian National Soccer League in 2018 and 2019 – year of the VAR introduction –, using home and away goals as the dependent variables in a bivariate Poisson regression model. The reduced-form was estimated by ordinary least squares (OLS), to control endogeneity caused by the number of fans present at the match – a control variable in our model –, because a bigger number of fans can improve the home team performance, but it can be related to the expectations that the home team is the favorite one at the match. The evidence suggest the VAR was responsible for an increase at the scoring chance of the away teams, while did not impact the goal chance of the home teams significantly.