The latest Journal of the Royal Statistical Society has an article on soccer referee bias:
The statistical evidence seems to point to a home team bias in the incidence of disciplinary sanction. This interpretation is consistent with evidence of home team bias in several other recent studies, which find that the home team is favoured in the calling of fouls, or in the addition of stoppage time at the end of matches. Finally, evidence is found of variation between referees in the degree of home team bias, and this variation contributes to the overall pattern of inconsistency in refereeing.
Most people involved in sport know: home referees tend to be biased for the home team. My colleague Alex Tabarrok similarly found that elected judges favor home plaintiffs against out-of-state defendants.
Why do we allow such biases? We could force referees and judges to travel further so they didn’t cover home teams. In sports, we could publicly evaluate and rate referees, via reviewing secret videotapes of random games. Would such evaluations be too hard, or is the bias on purpose, because fans enjoy home game wins more than they dislike away game losses?
i believe there is a bias against northeast teams when playing away.newcastle,sunderland and middlesbrough, it seems to me,get badly treated by referees and incidently,the media in general.i think our geographical location has something to do with it.split second decisions have to be made by the referee,and it is at these times when the bias comes in,although it may be regretted later.referees,though will not admit to mistakes.
Lots of fairly advanced econometric studies have been done on home field advantage in sports. The studies I recall show evidence that referee bias for home teams is small but measurable controlling for other important factors such as travel, field unfamiliarity, etc.
I've wondered for a long time how innate racism is. It seems so universal that it must be something we are born with. It's likely humans evolved to mistrust members of other clans for natural selection reasons. They do not share the same genes, so they would be seen as rivals for resources and reproduction opportunities. We might have innate negative feelings towards people who do not resemble us for that reason. Those feelings are probably strongest against those who are most different. If this is true, then "discrimation" and "bias" are the same thing.
Am I just stating the obvious?