The effects of referees on the final score in football

This paper examines whether there exists favouritism by individual referees in favour of the home team in Argentina’s first division football (soccer) league. We study 936 matches between 2008 and 2010, and run both ordinary least squares (OLS) and two-stage least squares (2-SLS) specifications. Using goal differential between the home and away teams as the dependent variable, we find that individual referees have a statistically significant effect on the score of the game, even after controlling for referee actions such as yellow and red cards, penalties awarded, and other factors such as team quality, crowd size, and crowd composition. Crowd size and composition do not seem to affect the outcome of the game