Harvard study uncovers soccer referee bias

By Reidar von Hirsch
Fans of football will be relieved by the findings of a new report soon to be released at Harvard University - all those hours in the stands cheering at the team and shouting at the referee have not been in vain.

A study by Harvard University professor, Ryan Boyko, has found evidence that supports a long-held assertion by fans of the game - that playing at home gives the extra push to ensure a victory.

Boyko himself is a life-long footballer on youth and amateur level, now turned football referee in the US College divisions. Feeling the pressure from the crowd he decided, together with his brother Mark Boyko, to look into whether this could be statistically proven.

"We decided to look into what research had been done before and found a number of studies suggesting that crowd noise can bias referees toward the home team but nothing that actually demonstrated it had real effects on the game," he said.

"The obvious difficulty being that it's difficult to show that it is the referees being biased as opposed to the away players playing dirtier or worse, but our idea was that if referee psychology was the culprit different referees would respond significantly differently to crowd noise and this is exactly what we found."

A look at the final table for the A-League last season shows that winners Melbourne Victory actually won more away games than home games - according to this study a damning verdict on their fans, or perhaps the fans of their away game opponents. The Victory won six home games and eight away games in the 2006-7 season.

But perhaps more importantly, the study also shows something far more worrying, that also the referees are prone to influence from the home crowd. The team playing at home is more likely to get a penalty kick than the opposing team.

"The most interesting revelation unrelated to referee home bias that we found was that how many cards a team received in a match seem to be most determined by how many cards opponents of the other team generally get, not on any characteristic of the particular team in question," Boyko said.

"Thus it seems that certain teams are better at drawing fouls from the other team and that this effect is more important even than a team's propensity to get in trouble themselves."

Another phenomenon in big league football that also can be explained by this study is a claim by fans of smaller clubs - that referees more often take the side of the bigger team. This might be true simply because bigger teams have bigger crowds. Crunching the numbers, Boyko's studies found that ten percent more goals were scored by a home team per 10,000 spectators.

"Teams that consistently draw more spectators do seem to have a bigger home advantage and our study was unable to definitively answer whether this was due to merely having more spectators or some other variable correlated with number of spectators, such as team or player reputations."

On a stadium like Old Trafford, where famous Manchester United just this week played a stunning 7-1 win against Italian number-twos Roma, this means almost 75,000 spectators, or an output of no less than 0.75 goals per match.

In the Asian Champions League and the European Champions League, the home advantage is taken into account in the tournament regulations with the so-called away-goal rule. However, this does not officially relate to the home-bias refereeing revealed in Boyko's study, but to the pressure a team feels from playing on hostile grounds. A team in these tournaments that scores more away goals than its opponent in a knock-out game proceeds if the overall standing is a tie.

When it comes to doing something about the home-bias, Boyko says referee training and assessment could be effective. Any kind of video refereeing, meaning the game is stopped to make sure what really has happened is one of the most controversial debates in football today - some say it would make it more fair, others claim it would slow it down and take away the magic of the game. Boyko agrees that it probably wouldn't be worth it to implement full video refereeing, as is common in other forms of football.

"One relatively simple thing that could be done is installing goal line cameras such that a judge in a booth can review perhaps the most important decision of all - whether a goal has been scored or not. In this instance it could be done in a matter of seconds and probably wouldn't break up the flow of the game much. In other cases it might not be worth trying to move decisions away from the referee on the field as it might slow the game down too much and take away from the essence of the sport."

"These are questions that should be thought about intelligently and addressed by the governing bodies of professional and international soccer in light of the evidence from our study and others' studies," he said.

Reidar von Hirsch is a soccer enthusiast and freelance journalist in Sydney, Australia.