The impact of differing audience sizes on referees and team performance from a North American perspective

The COVID-19 pandemic provides a natural experimental framework to comprehensively test the effect of crowds on both referees and players. We examine this from North American perspective, using data three major leagues: National Basketball Association (NBA), Football League (NFL) Hockey (NHL). In all leagues in 2020–2021 season, matches were played either empty stadiums or before diverse audience sizes. find that lockdown affects NBA NFL results, by lowering prospects winning expected scoring points home team, when games are without an audience. Conversely, does not substantially influence outcomes NHL games. also size game historical observations past decade, no measures force. Interestingly, larger increases chance visiting team for No significant match is observed Regarding referee decisions, spectators do significantly calls matches. As NFL, total number but prompt more biased decisions towards teams. Finally, leads favourable These results extend literature regarding crowd pressure behaviour players officials, with indication specific sports activity has pivotal role response cheering