Economists Find Racial Bias in NBA Refereeing

A new academic paper by Justin Wolfers and Joseph Price finds evidence of subconscious racial bias by NBA referees, although the effects are rather small:

Mr. Wolfers and Mr. Price examined whether otherwise similar black and white players had fouls-per-minute rates that varied with the racial makeup of the refereeing crew.

“Across all of these specifications,” they write, “we find that black players receive around 0.12-0.20 more fouls per 48 minutes played (an increase of 2 ½-4 ½ percent) when the number of white referees officiating a game increases from zero to three.”

Mr. Wolfers and Mr. Price also report a statistically significant correlation with decreases in points, rebounds and assists, and a rise in turnovers, when players performed before primarily opposite-race officials.

“Player-performance appears to deteriorate at every margin when officiated by a larger fraction of opposite-race referees,” they write. The paper later notes no change in free-throw percentage. “We emphasize this result because this is the one on-court behavior that we expect to be unaffected by referee behavior.”

I’m not sure exactly what to make of their findings without having read the whole paper, but an effect of 0.12 fouls per 48 minutes translates into just 13 fouls over an entire season (assuming a player is on the court every minute of all 82 regular-season games); I don’t doubt the statistical significance of their results, but a foul every 8-9 games would only be an important effect if referees were non-randomly assigned and most games had either all-white or all-black officiating crews, but neither is the case (77% of NBA games were refereed by a mixed-race crew over the period studied, which is a figure likely to increase as the number of black NBA referees is increasing). In other words, we would expect these effects to by-and-large cancel themselves out over the length of a season, even if individual games might be slightly biased by these effects.

As the Times account indicates, the study is probably a more interesting contribution to the debate over the role of subconscious/unconscious racism than it is in terms of its insight into NBA refereeing–doubtless to the disappointment of frequent ref critics like Mavericks owner Mark Cuban.

FILED UNDER: Economics and Business, Race and Politics, ,
Chris Lawrence
About Chris Lawrence
Chris teaches political science at Middle Georgia State University in Macon, Georgia. He has a Ph.D. in political science (with concentrations in American politics and political methodology) from the University of Mississippi. He began writing for OTB in June 2006. Follow him on Twitter @lordsutch.

Comments

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  2. James Joyner says:

    I wonder if there are a handful of players skewing the data. I’m only a very casual follower of the NBA but can think of four or five players known for thuggish play. All of them are black.

  3. carpeicthus says:

    James: Read the data — they’re not measuring black v. white players, they’re measuring the same players with different referees. Sounds like a solid study, but I also agree with Chris’s conclusion.

  4. Andy says:

    13 fouls over a season seems pretty significant. That’s two games fouled out.

  5. Brainster says:

    I’m concerned at some of the adjustments reported. For example, they “adjust” for the fact that centers foul more often than other players and are disproportionately white. Translation: They reduced the number of fouls called on white guys. They adjust for the fact that all-stars get called for fouls less than non-stars. But all-stars are disproportionately black (nine of the ten selected starters this year were black and the tenth was Yaou Ming), so they increased the number of fouls by black guys. And what the heck did they mean when they adjusted for a players “assertiveness on the court”?

  6. Well, it would be a big effect if some players always played before all same-race crews and some players always played before all opposite-race crews. But since they don’t, the substantive effects diminish quite a bit.

    The more I think about it, the more I wonder about the effects of partial separation on their results; when you control for race, height, size, “star power,” years in the league, and position on the court, I’m not sure there are enough players in each “bucket” combination to make reliable inferences. Who’s the white equivalent of Shaq or the black equivalent of Dirk Nowitzki?

    Race may also be functioning as a proxy for “playing style” here. Maybe white refs are slightly less tolerant of aggressive play, more associated with American players (predominantly black) than Europeans (almost all white), than black refs–perhaps an artifact of generational effects (I’d expect the average black ref is younger than the average white ref).

  7. Bugz says:

    Is no one even willing to ask the question, “Do black NBA players actually commit more fouls?”

    I don’t know if they do or not, but was the hypothesis even considered? Seems like maybe it should be considered, if only to eliminate the possibility, if nothing else.

  8. David L says:

    Given that that authors of this supposed study can not say which official called what fouls, in the case of any mixed race crew, the study seems rather inconclusive.

    Further, I skeptical of trying to judge human performance, and subjective opinion, based purely on box scores. Much to do about not much.

  9. […] Study of N.B.A. Sees Racial Bias in Calling FoulsAn academic study of the N.B.A. suggests that a racial bias found in other parts of American society has existed on the basketball court as well.  ARTICLE » ALAN SCHWARZ The New York Times Tuesday, May 1TAGS: •  The New York Times > Race   •  The New York Times > Harvard University   Who’s Blogging Most Relevant First Most Recent First Economists Find Racial Bias in NBA Refereeing James Joyner Outside the Beltway elap(‘1178077050’);A new academic paper by Justin Wolfers and Joseph Price finds evidence of subconscious racial bias by NBA referees… “Basically, it suggests that if you spray-painted one of your starters white, you’d win a few more games” Mark Thoma Economist’s View elap(‘1178079120’);The blog Politics, Economics, and other Stuff notes a new Justin Wolfers paper on racial bias among referees in the NBA: New Justin Wolfers Paper makes the NYT.. … New Justin Wolfers Paper makes the NYT, by Stefan: The NYT reports on the new Justin Wolfers paper: Racial Discrimination Among NBA Referees.More on referees Skip Sauer The Sports Economist elap(‘1178093460’);In today’s New York Times, numbers guru Alan Schwarz discusses a paper by Joe Price and Justin Wolfers on referee decisions in the black players get called for about .1 to .2 more fouls per 48 minutes played. Are NBA referees racist? Tyler Cowen Marginal Revolution elap(‘1178107828′);I wouldn’t have thought so, but Justin Wolfers, writing with Joseph Price, says maybe yes: …during the 13 seasons from 1991 through 2004… Some Law-Talkin’ Milbarge Begging the Question elap(‘1178059380’);A few law-related thoughts this week:1. There’s been a lot of chatter this week over the Supreme Court’s decision in the car chase case, Scott v. Harris … Not strictly about law (yet), but I found this interesting and wanted to pass it along: A new academic study says that white referees call more fouls against black players than against white players in NBA games. Related ArticlesReport: Study suggests racial bias in calls by NBA referees International Herald Tribune elap(‘1178103602’);An academic study of NBA officiating found that white referees called fouls at a greater rate against black players than against white players, The New York Times reported in Wednesday's editions.Study Suggests Racial Bias in NBA Calls The Associated Press elap(‘1178094720’);An academic study of NBA officiating found that white referees called fouls at a greater rate against black players than against white players, The New York Times reported on its Web site Tuesday night. BlogRunnerHomeMost Blogged 24 HoursTop StoriesAlan SchwarzSwitch-Pitcher Is Baseball’s Ultimate Specialistelap(‘1175829603’);DISCUSSION »Rebuilt Cubs Start Season by Putting Up For-Sale Signelap(‘1175574049’);In Baseball, Searching for Balance in the Scheduling Vortexelap(‘1174824002′);DISCUSSION »Wives United by Husbands’ Post-N.F.L. Traumaelap(‘1173873602’);DISCUSSION »Head of N.F.L. Panel on Concussions Quits Amid Research Doubtelap(‘1172713202’);DISCUSSION » blogrunner.com … e: feedback(AT)blogrunner.com … Wed May 2 08:51:04 2007 ET … Copyright (c) 2006-2007 The New York Times […]

  10. bill says:

    This study, the headlines and media reaction are yet another example of the insanity happening in this country when it comes to racism. The data from this exact same study found that: black players received fewer fouls per 48 minutes than white players, 4.33 to 4.97. The headlines should read WHITE PLAYERS RECEIVE 15% more fouls per game than black players due to racial bias. Read that again, white players recieve a half of a foul more per game than black players. Take this fact from the EXACT same study and create a headline that says there is racial bias towards black players. Huh??? How do you get that conclusion? WAKE UP PEOPLE!