Power (Dis)Play? Teams In Black Draw More Penalties
Hockey teams wearing darker-colored jerseys are more likely to be penalized for aggressive fouls than teams wearing white jerseys, according to new research. Teams wearing black jerseys in particular get penalized the most, according to an analysis that may offer a window into the hidden psychological dynamics of the ongoing NHL playoffs.
"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.
The psychologist said that teams that wore darker colored jerseys were penalized about two minutes more per game. The finding is based on an analysis of more than 50,000 NHL games over a quarter century. Players spend nearly a million minutes in penalty boxes in those games.
-- Based on historical game data from 1984-2010, researchers examined 52,098 NHL games over 30 seasons of play.
-- Teams racked up a total of 969,690 penalty minutes across these games.
-- The average team was assessed 1,528 penalty minutes in seasons when they wore black jerseys and 1,386 penalty minutes in seasons when they wore other colored jerseys. That's a difference of 10.2 percent.
While the link between jersey colors and penalties is correlational, Webster said it's likely to be more than mere coincidence: A 2003 rule-change by the NHL that affected whether teams wore white or colored jerseys for home and away games allowed researchers to conduct a quasi-experiment.
Before 2003, teams typically wore white jerseys at home and colored jerseys for away games. After 2003, teams wore colored jerseys at home and white jerseys for away games. There were some exceptions, but the change in uniforms meant that the researchers could disentangle the influence of the jersey-colors on penalties from the possibility that teams were being penalized more or less depending on whether they were playing in front of a home crowd.
Why The Increase In Penalties?
It is not entirely clear what's driving the link between darker colored jerseys and increased penalties. But Webster said there could be a handful of different explanations.
One possibility is that players wearing darker colored jerseys are more visible on the ice than players wearing white, allowing referees to spot fouls more easily. The trouble with that theory is that players wearing black jerseys in particular got penalized more than players wearing other dark colors — it isn't clear why black would be so much more visible on the ice than other dark colors.
A second possibility is that wearing dark colors somehow makes players more aggressive, which lands them more often in the penalty box.
A third possibility, Webster said, is that players were not doing anything different, but that the referees had unconscious biases against black and other dark colors.
"There is this very strong cultural association that comes through in how we think about colors in terms of white being associated with good and black with bad," Webster said in an interview. "Many of us are raised from childhood with some of these associations. And over time, we develop a kind of cognitive bias. That's been shown time and time again in social psychology."
In an earlier study, researchers at Cornell University also found a similar pattern of increased fouls among NFL teams that wore darker colors. The researchers conducted an experiment where they had high school and college students run two versions of identical football plays, wearing white uniforms in one version and black uniforms in the second version. Referees who later watched the identical version of the plays called fouls more often when the players wore black.
The research is to be published in the May issue of the journal, Social Psychological and Personality Science. Webster's co- authors are Geoffrey R. Urland of Boulder-based Toravner Research and Design, and Joshua Correll at the University of Chicago.
RENEE MONTAGNE, HOST:
And from the rough and tumble world of British media, we move to hockey. Last night, the Washington Capitals knocked the defending champion Boston Bruins out of the National Hockey League playoffs in a dramatic game seven overtime victory. This opening playoff round has been filled with upsets and also penalties. Nine players have been suspended so far for violent play. Now some research shows that hidden psychological factors play a role in how hockey penalties are doled out. NPR science correspondent, Shankar Vedantam, joins us often to talk about curious sorts of social science research. Welcome.
SHANKAR VEDANTAM, BYLINE: Hi Renee, how are you?
MONTAGNE: Pretty good. So, what is this new research about?
VEDANTAM: So, as a word of background, Renee - when a hockey player commits an aggressive foul, the referee can penalize a hockey player by putting him in the penalty box, and typically, this is for two minutes. And during that time, the player's team plays with only four men on the ice, while the other team plays with five men on the ice. This is called a power play and it's a significant scoring opportunity for the team that has more players. Now there's this new research by the psychologist at the University of Florida, his name is Gregory Webster. He's found that the color of the uniforms that the players are wearing plays a significant role in how often the teams get penalized. And in particular, he's found that one color gets teams penalized the most.
GREGORY WEBSTER: Teams that wore black jerseys were penalized more - significantly more - than teams wearing other colored jerseys.
VEDANTAM: And Webster has found that teams wearing black get an average of about two minutes more, per game, in the penalty box.
MONTAGNE: What would cause certain colors to get more penalties?
VEDANTAM: The short answer is, I don't think anyone knows. This was a very large study that has an empirical finding. It wasn't necessarily designed to answer the question why. That said, Webster has a few theories. The most obvious theory is that hockey is a game that's being played on the ice, and so teams that wear colored uniforms, the referees are more able to spot fouls because players wearing colored uniforms stand out more clearly on the ice. Now, one problem with that theory is that teams wearing black uniforms got penalized significantly more than teams wearing other dark colors. There's another explanation, which is that wearing dark jerseys simply makes players, somehow, more aggressive. That they're actually committing more fouls when they wear the darker colored jerseys, and that's why they're ending up in the penalty box more often. And finally, I think there's a third explanation. And that is that the teams wearing darker jerseys are the victims of, you know, unconscious biases on the part of referees. Hears Webster again.
WEBSTER: There's a very strong cultural association that comes through in how we think about colors, in terms of white being associated with good and black being associated with bad. Many of us are raised, from childhood, with some of these associations. And over time, we develop a, kind of, cognitive bias. And that's been shown time and time again in social psychology.
MONTAGNE: Time and time again, not, obviously, only in hockey then?
VEDANTAM: So, this has actually been demonstrated in several sports. Several years ago, there were researchers at Cornell University who conducted an experiment. They had high school and college football students, essentially run the same football plays. In some cases, the teams wore white uniforms, and in other cases, they wore black uniforms. And when the researchers showed the videos of these plays to referees, it turned out that the referees penalized the team significantly more when they were wearing the black uniforms, even though the plays were completely identical.
MONTAGNE: That's Shankar Vedantam, who joins us regularly to talk about research on topical issues. Tell him your theories about hockey jerseys on Twitter @hiddenbrain. And while you're at it, you can follow this program @morningedition. Transcript provided by NPR, Copyright NPR.