Post-game Reactions

Officiating has always been a strong point of contention in NBA circles. The flow of an NBA game can be largely influenced by the three referees on any given night. This afternoon at the Sloan Sports Analytics Conference in Boston, Tobias Moskowitz and L. Jon Wertheim presented their findings on the bias officials can exhibit in the NBA along with other sports, their study “Whistle Swallowing: Officiating & the Omission Bias”

Moskowitz and Wertheim looked at five sports in their study of omission bias which, in their words, is referees unwillingness to make incorrect calls rather than make incorrect non-calls. In their words, this bias is worse than a random mistake in officiating, which are predictable and tend to balance out over time. Omission bias however can be unknowingly and does not have the random tendencies to balance out over time. This philosophy is consistent with human psychology with the distinction people have between “doing harm” and “failing to rescue” with the latter being the much less egregious offense in many people’s eyes. The same goes for officiating.

So where does the NBA fit into this type of bias? The research showed a couple much maligned problems in the league are as big of an issue as many fans of the league would have presumed.

The first is star treatment. The study compared how likely officials were to call loose ball fouls on stars compared to non-star NBA players they were contesting in loose ball foul situations. The results were found over a 3 year study in which 1.5 million plays were examined in 3500 plus games. “Star” criteria was based on players  MVP votes. The results:

-42 percent of loose balls fouls called on stars in “regular” situation compared to 57 percent of the time on non-stars in plays.

-The numbers show a much more dramatic shift, favoring the star players when they are in “foul” trouble with only 28 percent of foul calls being called on them, a huge drop from the earlier 42 percent.

-When the roles are reversed however, and the non-star is in foul trouble, the numbers normalize again with 48 percent of the fouls called on the non-star compared to 51 percent for the star.

The other study involving the NBA involved a look at subjective calls (offensive fouls, traveling, double dribble, etc.) being made compared to non-subjective calls (kick ball, 24 second violation, etc.) over the course of the game. The tendency to want to let the players decide the game in close as well as late game situations showed itself once again in the form of omission bias, with the rate of calls falling dramatically from the 1st half to the 2nd half. Another even sharper drop in subjective calls was apparent in overtime games with the subjective or “judgment” calls. The non-subjective call rates remained very level over those time spans.

So what’s the good news about all this? It appears the omission bias in the NBA is not an isolated phenomenon. Research showed universal problems in officiating in all other sports researched including in the MLB, NHL, NFL and International Soccer. So while NBA fans may have something to complain about officiating in their sport, they can sleep a bit easier knowing that they aren’t the only ones that have to deal with the problem.

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Brian Robb

Brian Robb co-founded CelticsHub in 2009 and is the currently editor-in-chief. He is a producer and reporter at 98.5 The Sports Hub in Boston and also contributes to Boston.com and Bleacher Report among other outlets.
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  • DeVelaine

    I’m curious to know if they did any research on which refs are worse on which teams/players. Might put some logic behind the Duncan/Crawford feud which is always amusing.

  • DRJ1

    (1) Hard to understand some of this language. Did you make a mistake in the 1st sentence of the 2nd paragraph? => “Moskowitz and Wertheim looked at … omission bias … which is referees willingness to make incorrect calls rather than make incorrect non-calls.”

    Did you mean something like: “omission bias … which is referees’ UNwillingness to make incorrect calls as compared to their lower barriers to making incorrect non-calls?” (Hope so… otherwise, I must have missed the whole point.)

    (2) It doesn’t help me to know that referees in all sports have similar biases. The special problem for the NBA is that the referees have the greatest influence on both the flow of games and their outcomes in basketball, as opposed to the other major sports. The refs are often – usually – highly disruptive and grossly unfair to one side or the other, and that just plain sucks.

    And the really irksome thing is that there are easy solutions available. The technology for those solutions is already built into every NBA court in the country. All we need is to establish a “video referee”, with feeds coming in from all cameras plus instant playback. If that video ref is given final authority on all calls, most of the problems that drive us fans nuts would disappear overnight. This could EASILY be done, and would not affect the flow or speed of the game one whit, if implemented correctly. Why they don’t do this…. is really beyond me. I hate to think it’s because they want the continued ability to influence outcomes — so I would love it if somebody could present some alternate motive for failing to bring the NBA into the 21st century.

  • DeVelaine

    DRJ, I’m understanding “omission bias” as the refs being biased against not making calls. As in… Calling too damned many fouls when the teams should be allowed to play through. As a side effect of this, a lot of incorrect calls are being made, which sounds like the point of the study. I wasn’t there, so I can’t confirm this. But that’s just what BRobb’s post tells me.

  • DRJ1

    @DeV– Exactly why I think he (originally) did not write what he meant. Later in the 2nd paragraph, he writes that “doing harm” is considered much worse than “failing to rescue”, i.e., making a bad call is thought to be much worse than failing to make the right call, i.e., the bias refs have is IN FAVOR OF SWALLOWING THEIR WHISTLES, as opposed to making too many calls.

    And I see now that the text has been edited, so as to eliminate the confusion.

    I guess I have to accept the study that was done about this, but man, in 90%+ of games it sure feels like there are WAY too many BS calls, especially in first halves.

    But it’s certainly true that there are far fewer calls in 2nd halves.

    Bottom line: refs suck, all over the NBA. They need to solve this problem once and for all. I like my video ref solution. If they did that, or some permutation thereof, they’d gain MANY more fans, and a lot more respect around the world.

  • DeVelaine

    The video ref idea is actually a good one. Now the idea is to pitch it to David Stern in such a way that he thinks it’s his idea. That’s about the only way it would ever get implemented.

  • DRJ1, I have to disagree that the refs have more control in the NBA compared to any other sport. I think it’s the worst in soccer, where a wrong call, usually a penalty kick awarded or not awarded, is the deciding factor in a huge number of games. NBA is definitely worse than MLB and probably NFL, I have no idea about NHL. You’re right about video providing a pretty good solution, I think for all the sports, and it would probably lessen the abuse on the refs too.

  • DRJ1

    @Mike– Got me on soccer! Take your word for it.

    But given that your point is correct…. it’s STILL worse in the NBA from one (important) point of view…. namely that the refs in the NBA are the most GODDAMN FRIGGIN’ ANNOYING possible… because they’re there on almost EVERY play, ruining the game, preening and prancing around like we pay to see them and not the players.

    Sounds like in soccer, they determine the outcome, but at least they’re not ruining the game until the end. Plus we don’t have to look at their faces… you know, how long can you look at Dick Bavetta’s mummified face before you start vomiting?

    Most fans hate the refs. I was telling somebody the other day that if Bavetta, Salvatore and Crawford ever refereed the same game, they’d have to do a weapons scan on every Celtics fan entering the arena 🙂

  • @DRJ Your were dead on about my typo in the 2nd paragraph now. It’s been corrected, I apologize for the confusion.

    As for your guys points about soccer, I agree more control can be exerted there, but I think the key element to take out of this study is how much of this omission bias stems from human nature and not an inclination for/against teams or players. Now it could be up for rightful debate when narrowed to specific referees but the entire theory stems from this type of bias is a psychology concern in humans more than anything else. Unfortunately, officiating is one element in which its effects can be dramatically seen.

  • Dan

    I’m skeptical that anything could be done about refereeing. The refs have a bigger influence on games, well because they have a much bigger role than in any other sport.

    But just as the refs may have their biases (and some of them mentioned above like the ‘superstar’ bias are definitely real), fans also have their own biases. We’re inclined to view any 50/50 call against our team as ‘wrong’, when really we should expect that to happen half the time.

    So of course having a younger staff, maybe insulated more from personal relationships with players, would help. And you could even throw in a replay challenge or two. But it won’t ever change the fact that fans will be unhappy with calls more often in basketball than in other sports.

  • DRJ1

    @Dan– My experience with other fans, and my own feeling, is that all fans want is ACCURACY. Nothing more. Just get it right. When a 50-50 calls goes against us, I just shrug my shoulders… hell, I’m HAPPY when it’s 50-50, because too often it’s an OBVIOUS wrong call that the refs screwed up.

    Thing is, and what the NBA apparently fails to recognize (tho that hardly seems possible) — the advent of instant instant-replay and DVRs and multiple cameras means that WE FANS see every play perfectly now. WE have become the super-experts, in a sense, because we see every single mistake the refs see. In slow motion. How stupid is it that the fans have a better view than the referees?? Totally stupid.

    Until the NBA recognizes this (obvious) reality and catches up with it, it’s doomed to have a LOT of unhappy fans… plus many others who WOULD be fans but are too disgusted by the officiating.

  • DRJ1

    I meant… “we we see every single mistake the refs MAKE” (I hate correcting obvious typos, but that one wasn’t so obvious?)

  • Dan

    I agree with you in that I don’t think any reasonable fan wants the refs to hand their team the game. My point is that when you are emotionally invested in the game, you aren’t an objective observer at all and so what seems ‘obvious’ to you can be ‘obviously wrong’ to someone else.

    If you’ve ever watched a superbowl or big playoff game with a group of people split between the teams, then you know what I’m talking about: two otherwise reasonable people completely disagreeing about the same replay.

    And of course a small percentage of the time there really is a call so wrong that everyone would agree. But the calls that bother fans more are the more subjective things like offensive fouls, charges, etc. where there’s no simple fix like looking at the replay to see if the shot clock’s expired. And in those circumstances, people definitely have a bias towards their team. And even if it’s really slight, say you expect to get 55% of the calls your way, if the game’s called 50-50 both fans can be upset with the outcome.

    There’s also another bias at work here, which is that you’re more likely to notice and remember a bad ref, then a good one. This of course skews our view of what percentage of games are refereed well.

  • sternsfrozen envlp.

    All it takes to realize that ref’s in the nba are bad or all “rogue” is watching a couple of small market teams like Portland , Sacromento etc. The only way to correct the problem is to get rid of Stern or quit watching. I wont watch because it makes me sick to my stomach to see some of these kids get cheated.

  • sternsfrozen envlp.

    Oh and the fans dont make the superstars the nba marketing department does ):

  • DRJ1

    @Dan– Re your last sentence… it’s interesting, as far as I’m concerned, because for me, the refereeing in a game stands out when there is NOTHING to complain about. I will usually post something to that effect… “Hey, the refs didn’t screw up this game!”… because IT IS SO RARE. Really, I’m serious about that.

    Of course, I also remember the most horribly officiated games too… but it’s happened only about 1 or 2 times this season where the refs were not “typically bad”… defined as a game where you simply don’t notice them. Where they make the calls the need to make, and otherwise get out of the game’s way. That, we all know, is a rare event indeed.

    But… we’re probably dreaming if we think it’s gonna change drastically any time soon. Though we should give em credit for the small steps they have taken… like the expansion of video reviews. The big step, though… instituting true video refs… is still nowhere in sight.

  • bobo

    Im glad its being recognized more but i doubt if anything gets better…the NBA has become like politicians,once they get in they don’t seem to be held to the same standards as before they got there,

  • ohioceltsfan

    Please don’t mention the name “Bias”! It still makes every Celtics fan cringe!

  • Dan

    Ya I agree. It would be hard to stop the flow of every regular season game just to check on fouls, but in the playoffs when there is a commercial timeout after every possession, why not?

    When they check for toes on the line now, is it the floor officials or someone else?

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  • I agree with you, but do you think its really accurate?

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  • Wow, Excellent tips to know about the bias in officiating.If you have more information like this.Please update me time to time now.
    thanks for info..:)