Do Soccer Referees Display Home Bias?

This paper examines bias in soccer referees actions, particularly through their decisions regarding extra time added. We review the literature on principle-agent interactions, in particular as it applies to sporting contests, and isolate some potential causal mechanisms and hypotheses. We then test the derived hypotheses and find that while there some are supported indicating a certain degree of bias, this bias appears to be less than in previous studies. We also show that this is not related to the stage of the season; is not a function of the strength of teams, and appears not to be significantly related to crowd composition or support. These findings are at a degree of variance with previous research, and we buttress them with qualitative approaches, interviewing major actors in soccer and considering the role of professional formation in the two leagues as potential factors