How the pandemic removed the home advantage in sports

Lots of things stopped during the pandemic, including the home-game advantage in sports, according to a new study published in Frontiers in Sports and Active Living.

A team of researchers from the University of Salzburg, Austria, found that referees in European elite soccer leagues gave out more yellow cards to the home team when stadiums were empty compared to when the game was in front of a full, supportive crowd, dampening the home-field advantage.

The researchers, led by Michael Christian Leitner, analysed and compared the number of yellow cards issued in 1300 soccer matches played in the 2018–19 and 2019–20 seasons. In the latter, pandemic restrictions caused teams to play ‘ghost games’ with no audience.

While the home teams received relatively more yellow cards for fouls in the 2019–20 season, the number of cards given to away teams remained virtually unchanged, potentially because referees didn’t feel pressure from crowds.

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“We were particularly surprised by the fact that the home teams in ghost games suddenly received so many more yellow cards for fouls,” says Leitner.

“We want to emphasise that our work is no general criticism of referees of any sport. The pressure on match officials is unbelievably high nowadays and the task is enormously demanding. We are enthusiastic sportsmen ourselves and respect the work of referees above all.”

Leitner suggests that the study shows more about human behaviour and the psychology of peer pressure than it does about the ability of a ref to make the right call.

“From an evolutionary point of view, we humans are pack animals and therefore our decisions depend strongly on our environment, the situation and other people present,” he explains.

“By investigating these specific ‘weak points’ in the human psyche – resulting in conformity and biased decision making – we strive to develop effective psychological interventions and countermeasures.”

The authors suggest that training tools that target how to deal with this pressure, such as immersive VR technology for simulating crowds, could help referees make consistent calls. VR has already been successfully used for training in some sports.

“So why not use virtual reality to prepare referees for games with several tens of thousands of fans?” says co-author Fabio Richlan.

“With virtual reality we have a technology at hand that can help (sports officials) to prepare for these challenging situations and train realistically and systematically in advance.”