A systematic review of the literature on video assistant referees in soccer : challenges and opportunities in sports analytics

Refereeing in sports is about fairness. The referee's job is to balance what the player with the ball thinks is fair with what the player trying to take the ball thinks is fair. Referees are judges on those two opposite opinions. Football (soccer) has massive global appeal and fan interest. Some football championships now use Video Assistant Referees (VAR) to help the referees make correct decisions. This study reviews the literature on VAR in football using the Methodi Ordinatio. Methodi Ordinatio is a methodology used to select and rank relevant scientific papers combining the impact factor, number of citations, and year of publication. We present a case study about the distance the VAR officials cover in the main Brazilian football championship (Brazilian Serie A). This study adopts the p-medians method to analyse the impact of opening VAR operation rooms in the distance covered by the professionals travelling to officiate matches. The locations of VAR operation rooms were obtained, and applying these locations in the first ten rounds of the Brazilian Serie A season 2021 would possibly reduce about 70% of the distance covered by the VAR officials travelling compared to the total distance performed.