While thinking about the recent discussion about uniforms, and reading about our games from last year which seemed to hinge on particular calls by referees, I wanted to put a post up during these football doldrums about perceptual bias, the power of home field advantage, and why we don’t want mostly black uniforms, despite how bad a@# we would look in black and blue. This post is not about the Xs and Os of football, but the degree to which referees are fallible, like the rest of use, and how we can leverage that fallibility.
Most of the research comes from soccer (the other football), and while I largely ignore that spectacle, in which whining about a non-injury is elevated to a virtue, the fan base can give American Football a run for its money. The other data set comes from Hockey - and I think they know a thing or two about fights and penalties.
There are basically 3 points I want to make about bias when to comes to referees. 1) they penalize teams that look mean (wearing black) more than those that don’t; 2) they are more quick to call a left to right play (how we read and thus inclined to formulate a decision) than right to left play; and 3) they cave to social pressure- which means the home crowd matters. None of this should come as a surprise, but what might come as a surprise is that this bias is measurable.
Color of Jersey -
If one team looks more menacing than then other, then that team gets more penalties. "When teams switched to wearing colored jerseys at home games, they were penalized more than when they wore white jerseys at home games... these quasi-experimental findings suggest that black jerseys are associated with more aggression and that white jerseys are associated with less." Thus, "teams that wore black jerseys were penalized more, significantly more, than teams wearing other colored jerseys," said researcher Gregory Webster of the University of Florida, Gainesville. (See www.npr.org—power-dis-play-teams-in-black-draw-more-penalties, and http://spp.sagepub.com/content/3/3/274).
A finding that is probably harder to leverage is when a referee views plays from left to right rather than right to left. It seems that if that referee grew up reading from left to right, then they are more confident making a call in that same direction. However, if it happens the other way, then the offending team might get a break. “Distinguishing between a fair and unfair tackle in soccer can be difficult. For referees, choosing to call a foul often requires a decision despite some level of ambiguity. We were interested in whether a well documented perceptual-motor bias associated with reading direction influenced foul judgments. Prior studies have shown that readers of left-to-right languages tend to think of prototypical events as unfolding concordantly, from left-to-right in space. It follows that events moving from right-to-left should be perceived as atypical and relatively debased. In an experiment using a go/no-go task and photographs taken from real games, participants made more foul calls for pictures depicting left-moving events compared to pictures depicting right-moving events. These data suggest that two referees watching the same play from distinct vantage points may be differentially predisposed to call a foul.” See http://www.freakonomics.com/2010/07/29/a-clue-to-referee-bias/).
The last finding is my favorite: An aggressive fan base has its advantages, so leave your wine and cheese at home and stand up and yell to give those referees something to think about. It is a long walk to the car. “Those, who are appointed to be impartial, tend to favor the home team as they systematically award more injury time in close matches when the home team is behind. Further evidence for similar home bias comes from referees' wrong, or at least disputable, decisions to award goals and penalty shots. The severity of social pressure, measured by the crowd's composition and proximity to the action, determines its effect.” (See http://ftp.iza.org/dp755.pdf).
I want to end this by saying that my hat is off to referees. They must love the game more than the average fan, are only noticed when they are suspected of an error, and are they easy scapegoat for those fans least able to acknowledge that their team s@#ks. However, if their call is going to biased, I want it to be in our favor. I think we are due.