I'd just like more talk about sports in general on here, it's a nice break from the really heavy stuff in society. I'll be pretty excited if this is a beat that Maya is on regularly here.
Thanks! I really like writing about the ways that sports intersect with economics (like this post) and politics, so hopefully I can contribute more on these topics in the future.
"RAPTOR says that Paul is still better than Beal straight-up."
"Yeah, I mean at Beal's salary he seems worth less than zero" (in reply to "Yeah the Suns are making a mistake. Biggest problem is that Beal’s contract is just way way too big")
Jun 19, 2023·edited Jun 19, 2023Liked by Maya Bodnick
Matt used to engage in fairly frequent basketball blogging back in the day. It's good that his operation's expansion allows for diverse expertise. I agree—informative article. And belated welcome to Maya Bodnick.
It's nice to have some out-references to UK topics like Soccer (or, Football, as I would natively call it. Or 'the footie').
There's a good 'long read' from the Guardian as this relates to UK Soccer which more-or-less says that the home-team advantage and underdog-bias (though it's a bit more nuanced than that) are the game and refereeing 'working as intended' or maybe 'the way the game is meant to be played' (unlike the 'superstar bias' these would not provide any particular team with an overall advantage). Of course the rules-as-written implicitly include any difficulty or bias in enforcement, and were arrived at because they produced an entertaining and profitable sport.
Super interesting. I didn't dig into football as much although there's LOTS of literature on it, but it's my impression that football officiating has not gotten much better (as NBA reffing has). I wonder why this is the case and also if online scrutiny has had an impact.
To quote from the Guardian article: 'Once, when Rosetti experimented with using VAR to review every incident in a single match, he found seven penalties and three red cards, according to a strict reading of the laws of the game. “But this is not football,” he said.'
That is to say, the rules as written are not and never were intended to be enforced by 'the eye of God', but rather by fallible and biased human beings.
Strictly rules-compliant officiating would not be 'better' - it would create an entirely different game from the profitable and enjoyable one that currently exists. The goal (heh) seems to be to reduce specific incidences of extreme public controversy using VAR (Video Assistant Refereeing).
Of course the game has evolved and will continue to evolve as sometimes-surprising technologies are deployed, but evolution is the key - popular and profitable changes will be kept, unpopular and unprofitable ones will disappear. Here's another Guardian article all about pitches and groundskeeping, for example:
Football is a difficult sport to officiate because there are tons of judgment calls (pass interference, holding, and roughing the passer being the most notorious) and also has calls that depend on viewing multiple attributes of the play ("completing the process of the catch" has been a particularly vigorous discussion of this).
There's another big, and obvious, difference between soccer and basketball: the amount of scoring opportunities. If a ref messes up a penalty or handball even in the middle of the first half, it could very well impact the outcome - it's hard (but not impossible) for any single refereeing error to sway the outcome in a basketball game, especially now the the NBA has the automatic review in the final two minutes of the game.
I loved the stats across different sports. The most amazing thing is that the home field advantage appears smallest in baseball. In baseball, unlike other sports, the rules literally favor the home team (batting last lets you know if you need one or more runs and to adjust tactics accordingly). Baseball also has non-standard fields which allows for (1) local knowledge of unique aspects, and (2) tailoring a team with character that best fit the park.
In baseball, the weakest major league team can beat the world series champion 25 or 30 percent of the time. Homs friend advantage appears small because most games are closer to 50/50 propositions than in other major sports
I'm not sure how that would work. I would expect if the base rate for "who wins in a fairly adjudicated game" were closer to 50/50, then the impact of slight biases on win rates would be greater, not smaller, because there are fewer other sources of variance. And I'd expect that if some teams are dramatically better than others, then when the better teams play away games, it would take truly blatant bias to make them lose when they would have otherwise one.
I think the reason is essentially unbiased officiating. If NBA home field advantage is largely driven by biased officiating, its reasonable to expect little home field advantage to be caused by less bias. Baseball has far fewer pure judgement calls then other sports. What meets the threshold of a foul is far more subjective than was a pitch in the strike zone or was the tag applied prior to the runner touching the base. By far the most important officiating in baseball is ball-strike calls, and basically since 2000, the MLB has tracked every pitch and told its umpires which pitches were misses. Only the best ball-strike callers ever make it to the majors to begin with.
Haha, I actually wrote another comment saying this same thing about hockey, which like baseball also has rules that favor the home team, and which also has a surprisingly small home team advantage (it's also a notably extremely fast-paced game so I'm not sure Jasper's slow pace explanation makes sense!)
To me the weaker home field advantage feels intuitive in baseball, because the slower pace of the game renders the crowd less impactful (they're also further from the action than in basketball), and the fundamental officiating activity—calling balls and strikes—likewise (to me at least) seems far less susceptible to home crowd effects than the officiating duties of North America's other professional sports leagues.
IDK if anything calling balls and strikes seems like it could be quite susceptible to this seeing as the home crowd boos for any pitch that goes against them, no matter how close it is and on actually borderline pitches umps could very well succumb. I think the officiation of balls and strike has less bias than in other sports because they aren't judgement calls (in theory). There is a strike zone defined by MLB which they can track very precisely. Plate umpires receive reports of their misses after every game and only the best ball-strike callers ever make it to the majors. I wouldn't be surprised if other types of calls in the MLB (tag plays, check swings, etc.) showed far more bias because of their less precise nature.
Referee bias sounds like it was great for fans for the same reason it was great for the NBA, and it only became not great when they were given the tools to know about it.
Now they fixed it and everyone is worse off. Absolutely fair games aren’t really beneficial overall.
It's corrosive. I'm not a fan of any of the teams, but I'll always remember when the Trailblazers with Scottie Pippen and the Kings with Chris Webber seemed obviously robbed by the refs in deciding playoff games against the Lakers.
There's probably a reasonable balance. Even though I describe ref bias decreasing, it definitely hasn't completely subsided. Where we are now seems pretty good bc it's gotten a lot less egregious while maintaining some judgement that improves the experience of watching games.
Yeah, the game was way more physical in the past with centers dominating by scoring inside the paint. Now the NBA's dominant center has the skill set of a point guard. Even average centers now have to shoot and defend further from the basket, even beyond the 3 point line.
Yes, this was my feeling as well. This article does a much better job explaining why the bias exists and what it's worth in points terms than it does in establishing the fundamental question of why the bias is a problem in the first place.
The curse of accuracy is very visible in soccer as well, where VAR calls now lead to goals being disallowed for reasons like the attacker's knee being a fraction of a centimetre past the defender, when previously goals like that would have been allowed to stand and people would have been able to celebrate rather than wait for a computer decision. It's not at all clear that fans are better off.
Sounds like you take issue with the offside rule moreso than its enforcement.
The flip side of offside decisions disallowing close but technically illegal goals is goals being disallowed for being offside when in reality they were onside, which happened a lot more in the past.
Overall offside VAR is good for the game, because enforcing the offside rule correctly without tech is pretty much impossible. Close offside calls involve the linesman hearing the ball being kicked and then judging the movement of the most explosive players in the world and keeping track of their arms and legs, and keeping track of one or more opposing players, all at the same time. It's impossible for their perception to be so fine to do that correctly, and IMO those calls used to pretty much be coin flips before VAR.
VAR has made more judgement-oriented calls arguably worse, because in the past the referee could always claim they missed something or had their view blocked or didn't see a foul in perfect detail. Now, if they make a call that differs slightly from a previous call or even one made by a different referee in another match, they are IMO much more under the microscope and can't get away.
Tight enough offsides are still judgement calls, they're just made in a booth far away. The precise moment the ball stopped contacting the assister's foot is hard to measure.
The presumption should be in favour of allowing goals with only visibly clear offsides brought back; if it can't be seen by the naked eye it shouldn't be offside. There's nothing worse than being in a ground watching a game and not celebrating a goal because defenders complain about anything at all and then VAR look for reasons to rule it out.
Then you get into the question of what a "visibly clear" offside is. And with needing to track the ball and so many players moving so quickly, even if you go with a really lenient standard like that, you're going to get missed calls where the offside player was half a body in front of their opponent (clearly against the rule), and calls where a player in full sprint is just onside a player not moving, but to the naked eye still looks offside.
I agree the delay in decision-making takes away from the fan experience, but so does being the victim of a blown call (and to my knowledge, England fans have been complaining for longer about being robbed by the ref in Germany in the 2010 World Cup (or Irish fans about Thierry Henry's hand of God) than they have any drawn out VAR call.
I think that the sensors inside the balls during the last World Cup could accurately capture the moment the ball was touched. I remember that particularly from that game where people were trying to figure out if a goal should be awarded to Cristiano Ronaldo or not, and I think the sensors said that he hadn't actually touched the ball (that was going in anyway). I expect that such balls will be used in more and more games in the years to come. And I also think that the offside line was automatically drawn by computers too.
On soccer, the offsides rule needs to be reformed. It shouldn’t be ok to simply wait in your opponent’s penalty area for a long ball. That would be too easy. However, once a team has worked the ball into scoring position, offsides is a silly distraction.
A rule that “offsides shall not be called based on a pass that began within 22 yards (the top of the penalty arc) of the opponent’s goal line” would be a huge improvement and would create more scoring
No, I mean a physical line on the field--something like extending the front line of the penalty kick box, or further back if appropriate. A moving line on TV would be good for viewers, but not helpful for players and officials. Maybe technology could some day find a way to put the moving line on the field without being distracting, though!
I indeed don't like having to wait to celebrate a goal, and I don't like millimeter offside goals either. However, I think this problem can be solved while keeping the VAR by increasing the thickness of the lines, and I hope that we'll eventually go there.
This is a valid perspective. I think there were a lot of forces supporting ref bias -- ref psychology, league profits, and (often) the enjoyment of fans. You're right that these biases profited the NBA because they usually made games more fun for fans:
-As a hometown fan, you want your team to win more at home b/c it makes it more desirable to go see games in person
-Most people like to see stars have amazing games
-Close games/series are also fun
With that said, I think there is a strong argument for fair officiating. It's great when the game is a spectacle and aligns with what I want to see as a viewer, but at the end of the day, I want the team that played better to win. When League credibility around this is really low, it actually does harm viewership/fan enjoyment. Just look to how sports like professional wrestling which are very skewed get much less viewership b/c it doesn't feel like a fair competition. NBA Twitter has blown the lid off of this problem and forced the NBA to readjust its profit calculus to make games more fair. Does that have downsides? Yes. But in the long term, fairness makes for better games.
I agree that the most corrosive bias is when calls influence the end of games. Good news on this is that bias tends to decrease in the 4th quarter, although a close game bias persists (https://papers.ssrn.com/sol3/papers.cfm?abstract_id=1377964). I am super happy with the League introducing the Last Two Minutes report b/c I think this creates some important transparency around high stakes calls that can swing the outcome of a game.
I'm not wild about placing extra emphasis on the end of the game, because bad calls early in the game can badly influence future actions later in the game. Probably less so for a frequent scoring game like basketball, but more so for less frequent scoring games like soccer, hockey, or football.
Yeah. Even though bias declines at the end, if the 2 point avg. advantage to home court teams was given in the first 3 quarters, the damage is already done! A lot of people in the comments have been defending bias, but I think at the end of the day when it's transparently exposed it's basically indefensible -- both on principle and from a viewership-enjoyment perspective. I value fairness, and I know a lot of people agree with me. Just look at how incensed NBA Twitter is 24/7 about calls they view as biased. The League benefits a lot from looking credible and fair.
At some point, unfairness makes sports leagues lose fans -- like the fact that everyone knows professional wrestling is super biased. I think NBA ref bias is less stomachable in the age of NBA Twitter and lots of data access, bc it's harder to just look the other way. There's precise video clips and data analysis revealing this bias. For example, with home bias, it used to be easy to dismiss it as due to travel, scheduling, etc. But now the data has definitively shown that ref bias is the cause. Can we really tolerate these biases now that they're out in the open, as opposed to a period of more blissful ignorance and speculation? I think the NBA has concluded that bias is a problem and will cut into profits unless it's resolved.
I’m less familiar with basketball, but I wonder what they could do to make games more competitive without violating the fairness issue and thus losing faith of fans?
I wonder if this would be seen as a more fair way to create this outcome than biased officiating. Probably (bc it's uniform), but I still think fans react to pointed rule changes like this. Case in point: the changes around the order of Playoff game locations and how this impacted the legnth of the Playoffs -- https://www.jstor.org/stable/40325820
I'm fine with that but I would imagine you have to be kind of subtle about it. If you just had a mercy rule at 10 points I don't think fans would like it.
The NFL seems to have managed this very well but the NBA's task seems much more difficult. But I'm not super knowledgable about basketball so maybe there's tons of options I'm not thinking of.
Yeah I think that makes sense, my point is just that this doesn't necessarily translate into a super popular product so it probably will not be the north star for any pro sports league.
Yeah perfect is the enemy of the good here. It’s my belief (unpopular with my friends) that instant replay has been really bad for sports and sapped some of the fun out of them.
I was going to have this hot take but I see it's lukewarm at best.
I would not be surprised if increased sports gambling has an influence on public opinion. I'm sure the oddsmakers take referee bias into account but gamblers playing a spread would have different opinions of end-of-game free throws than home team fans would.
Glad to see someone is picking up the torch for fivethirtyeight. It wasn’t on my favorite subject, but the research and arguments were so compelling I read to the end.
It's like having 538 with the Slow Boring comments section. Definitely would support a weekly sports-themed post, even if it's just one of the brief open discussion posts and not a full article.
Should be seeing some mid-season baseball data covering the rule changes, for example.
Also Matt's sports opinions have been... somewhat more poorly informed relative to his average opinions about everything else. So if Maya is raising the bar, all the better!
Washington sports have been poorly PERformed relative to everything else so it's just statistically expected. (Yeah, yeah the Nats had 2019 but they've been bad recently. And Matt can't compete with Dara Lind on Nats fandom.)
Jun 19, 2023·edited Jun 19, 2023Liked by Maya Bodnick
Outstanding introductory article, Maya!
One of the most frustrating things I deal with in interaction with fellow sports fans (interactions that are mostly positive, because people who watch sports are pretty great people overall) is the domination of conspiracy theory believing that goes on when a call doesn't go the way of the team they want to win. Far too many seem utterly convinced that there's some scheming puppeteering going on in the most upper annals of league executive offices to rig games for whatever fans believe is their sinister motive. This was an elegant way to explain how problems we see with officiating have a less sexier answer: they're humans that like any other are flawed, and let their flaws seep in when not checked and verified. I'm going to keep this article in mind when conspiracy theorizing is going on.
In addition to what you've added, two other thoughts as to how to continue to improve officiating:
--In the vein of another Slow Boring theme, automate as much officiating as possible. Some rules are heavily judgment calls where this might not be possible, but things like crossing an out of bounds or offside line, verifying 2 pointers vs 3 pointers, and so on, are clearer. Above all, I for one would welcome new strike zone overlords to baseball, and it would get rid of a lot of arguments in that game.
--Implement a sky judge as an additional check against biases officials on the field may have that can see the whole court from above, and also has the benefit of instant replay to look things over after the heat of the moment of play, and relay any feasible corrections down to the officials on the floor. This I think has the best potential in a sport like football, where there's regularly plenty of time after each play to review and digest what happened, and make corrections as appropriate.
I think psychological biases are the simplest explanation for ref bias, but it is a little suspicious to me that they align so well with NBA profits. Def not a proponent of "league is rigged" explanations, but I think historically there's probably been some subtle incentives for bias (i.e. what Price shows with regard to game assignments). Very important to soberly analyze this and not just allege conspiracy theories!
1) Love the automation idea. Tennis has started doing this pretty successfully I think.
2) How would a sky judge work? Would they be able to overrule refs on the court in real time?
Yeah, tennis is a sport where automation naturally works really well, lots of easy bright line calls in that sport.
With regard to overruling, this is something that happens all the time on the field when two officials may have seen something different, or are uncertain about what they saw and want a second opinion. They talk it over with each other, and quickly come to a collective conclusion about what to call. The sky judge just adds another official that's equal among all other officials in this ability--this official just has a different view from above and just needs to talk things over remotely.
I think it was simply inaction — the league being aware that the biases exist, but doing nothing about them (until recently) because they happen to align with incentives.
I’m still upset about just the number of foul calls overall. High-scoring games can be fun but things have swung too far in favor of offense. Let them play more, give defenders a chance, and do something about the calls that allow offensive players to bait defenders into shooting attempt fouls when they are not realistically in shooting position/have actual shots.
Jun 19, 2023·edited Jun 19, 2023Liked by Maya Bodnick
I agree with this sentiment in general, with one exception: I'd actually like to see the league tighten up the rules on defenders drawing charges. A lot of calls in favor of defenders look to my eyes like non-basketball plays. Like, there has to be way to reward a defensive player for legitimately getting into position and being willing to take a charge (aka penalize the offensive player for illegal contact). But the emphasis seems to have swung too far in favor of the "gotcha" play by the defender. Seems a bit gimmicky to me, and not in keeping with what this fluid game is supposed to be. Maybe more strongly define a time requirement for the defensive player to be planted, or consider changing size of the restricted area?
It’s certainly one of the main rule changes that swung things in favor of offense initially but I think it’s how it’s now combined with these other trends in favoring offense plus big-picture things like analytics people realizing 3s are the way to go that have just pushed everything too far in favor of O since it affords a lot of spacing for guys that can pull the trigger with ball in hand. I’m not saying I want the old days where a strong defender can just push an offensive player where they want to force them with hand checks, necessarily. Simply that rules always need to be reevaluated in context and it’s time to do something to rebalance. Do you’ve any particular takes on hand check or the topic broadly?
Just one quibble: you can’t compare changes in home team advantage in the playoffs without taking into account the relative strength of the two teams, because more games will be played on the court of the higher seed. The disparity in strength can vary by season because of differences in general competitiveness across the league. In a season where there are some very strong teams and below .500 teams are making the playoffs, the home court advantage will be larger than a season where teams are more evenly balanced
This issue is perhaps even more pronounced in college sports. Non-conference games are overwhelmingly held at the home field of the stronger team (e.g., in football, UNLV and Bowling Green play at Michigan this year; a Michigan/Bama/OSU would never travel to play those types of teams). That said, you can solve this problem by restricting your sample set to conference games, so perhaps these studies did that.
Also, ref bias is higher stakes in college MBB bc March Madness is single elimination. This makes you appreciate the 7 game series! Individual biases / bad calls matter less
Totally agree; I think some of the studies I looked at tried to adjust for team performance/strength but this is obviously really hard to do. Definitely gets at a broader issue around how hard it is to mitigate the enormous amount of potentially confounding variables around officiating.
“The data is clear: referee bias is the number one cause of the home-court advantage.”
Whooooaaaaahhhh....slow down, Turbo! Sorry, but I don’t think you (or the research and stats you’ve cited) have in any way made this case.
I will absolutely concede that superstar bias is real (although as a Mavericks fan, I wonder how this works with superstar mega-whiners like our beloved Luka Doncic), but seems to me you’re totally dismissing other - more likely, in fact - possibilities that explain the home-court and come-from-behind advantages: that teams play harder and smarter for their own fans and they play harder and smarter when they’re trailing...
Why is it refs worry about getting screamed at by hostile hometown fans, but the same anti or pro hollering doesn’t impact the players themselves?
The idea that play shouldn’t vary because ‘arenas are standardized’ is baloney! What the hell foes standardized mean? This isn’t baseball - the court is the same, but sight lines, lighting, music, smells, altitude, locker rooms, arena logistics, security guards, parking lots...I admit that big American cities are homogenized, but - in the words of Robert Plant - never let’em tell you that they’re all the same. To me it is intuitive that any team playing 50% of games in a single venue and the other half scattered among 29 other barns will gain a level of comfort with the most frequent setting.
As for come-from-behind bias - isn’t a more likely explanation a simple reversion to the mean? The Kindergarten version is: teams fall behind because their opponent shoots unusually well, or because they shoot unusually poorly...but over the course of a game the hot teams cool and the cool teams heat up.
At any rate - basketball is a talkin’ sport, and I’m sure the discussion will be lively.
"Moskowitz and Wertheim found that this combination of disparities gave home teams an average of over 2.5 points per game and accounted for three-quarters of the home-court advantage in the 2000s. They also show that other commonly cited explanations — weariness from travel, unique arena characteristics that the home team is comfortable with, and unfavorable scheduling for the visitors — fall short. Visiting teams may be tired from travel, but home teams beat visiting teams at the same rate even when they are based in the same city and travel is marginal. And in the NBA, home teams don’t benefit significantly from unique arena characteristics because arenas are mostly standardized. Moskowitz and Wertheim do agree that scheduling is an important contributing factor to home-court advantage — road teams play more tiring back-to-back games than home teams do. But the authors conclude that this only accounted for one-quarter of the home team advantage in the 2000s... As you can see in this graph from FiveThirtyEight, home teams gained an average of almost two points per game when they played in front of crowds versus when they played in empty arenas. However, comparing free throw percentages at home vs. away helps separate these factors. If crowd cheers really encouraged the home team and boos really got to the heads of the visitors, we’d expect that teams would make more free throws at home. But during the 2020-2021 season, teams made free throws at very similar rates at home vs. away. In fact, many teams even shot better when they weren’t at home! It certainly seems that hometown crowd pressure does not have a huge impact on the players and that the crowd’s impact on referees is the true source of the home-court advantage."
Anyways, I totally hear you and a lot of people share your perspective! I think you should check out Scorecasting, the book I mention, bc they make a more persuasive case than I do for the dominant role of ref bias. I tried to summarize and substantive their key points here, but your objections make sense. There are so many different factors going into home court advantage that it can be hard to disentangle them. My impression is that ref bias is the #1 cause, but reasonable people can disagree.
No. Reread her article, she is citing other authors:
> Moskowitz and Wertheim found that this combination of disparities gave home teams an average of over 2.5 points per game and accounted for three-quarters of the home-court advantage in the 2000s.
If you have issue with the source paper fine but don’t say she just made this number up bc she didn’t.
I didn’t say she made the number up. I said she’s making assertions - based on the book and some papers - that I’m not buying. To make her point requires that we all completely swallow these sources’ conclusions - and I can’t get there with her.
That women's final was officiated so, so poorly. Not that LSU didn't deserve to win (they did!), but the refs kept making the game about themselves. Which, more than anything, is what fans object to.
This piece definitely contains some interesting information.
However, NBA refereeing is still in a place where many engaged fans view the games as being openly rigged. There are still refs who were involved in the gambling scandal that are refing. Scott Foster has the nickname "The Extender" because of the belief that the NBA deploys him to extend playoff series.
The point being is that the officiating in the NBA is bad to the point that conspiracy theories are pretty mainstream among fans.
One thing to note is that much of the piece focuses on bias officiating rather than just poor officiating. This makes sense because it is seems more possible from a data angle to see if something is bias than if it is simply a bad call.
Regarding the L2M report, in my experience these to little to quell fans anger or distrust of the refs. I believe the NBA says they review the whole game in a similar way but only release the 2 min version. It also allows the refs to appear more bias when they do things like apologize to the Lakers.
Also, I believe both Lebron and Curry actaully shoot very few fouls relative to their stature in the league. Curry possibly because of his shot selection, Lebron perhaps because of his size. These two are perhaps not the best example of people who get superstar calls. (Foul baiting aside, Embid, Luka, Giannis, Trae)
One interesting bias to look at might be size bias. I believe it was found in soccer that larger players were officiated more harshly but it a common complaint that big men are allow to be fouled quite hard without calls which sometimes encourages flopping, see Embid. Jokic being a pasty White makes it easy to see how beat up his arms are after games.
In the 2nd to last paragraph, "he NBA claimed that it hadn’t made any policy changes related to racism bias"
1) I think fans will always complain about the refs, but I expect the complaints may decrease a little in coming years b/c bias has legitimately gone down. It's natural for there to be complaints but if the refs are mostly fair, that's not something for the League to worry about too much.
2) Interesting point on poor officiating; but that should come out in the L2M reports and general reviewing of data. I think the transparency from this + disciplining process are strong incentives for referees to clean up their act; the data has shown that this truly has been the case in recent years.
3) I read somewhere in my research that size bias wasn't statistically significant in the NBA, FWIW. Obviously there's some confounding factors there with star bias
Good article! I agree completely. I’m more of a baseball fan than basketball, but enjoy all sports. The increased transparency and accountability caused by improved broadcasting technologies and the internet have improved tall sports. For example, I love the “ump scorecard” on Twitter. Automation is the answer, where you can do it. They need to implement it wherever they can. VAR has made offsides calls in soccer almost completely objective. Baseball needs to follow suit with ball/strike calls. I’d love to see this level of transparency and accountability in our public and private institutions. It works. And, if you do it right, people will compete with each other to be the least biased and/or most compliant. Humans are naturally biased, but they also are naturally competitive. That’s why we love sports so much. Creating a fair playing field focuses our attention on competing.
VAR can help objectively determine whether a player is beyond the offside line, but it still relies on humans to decide where to draw the offside line. It can help objectively determine whether the ball struck a player's arm, but a human still needs to judge the player's intent. VAR doesn't make officiating more objective - all it does is shift the controversy from the officials on the field to someone sitting in a room somewhere.
As this is more of a political/policy Substack, if we think of the media as referees, what are some things we might expect to boost ratings due to more interest or as a result of natural root-for-the-underdog tendencies or wanting to be entertained/engaged? An incumbent President has a big advantage, so we might expect to see:
1. more emphasis on polls showing the President is in trouble due to negative favorability
2. emphasis on any poll showing a strong primary challenger to the President or movement in that direction
3. emphasis on polls showing the challenging party having a close race, or any move in that direction
4. more negative coverage of whoever is in the lead in every stage
5. a desire for more debates, and speculation about VPs and brokered convention scenarios, even though a VP has not been replaced since 1944, and before that, 1864, and we have not had a brokered convention in the primary election era (since 1970s)
This was a well-written and enjoyable article. It’s nice to get hear about something a bit random like this from time to time.
I'd just like more talk about sports in general on here, it's a nice break from the really heavy stuff in society. I'll be pretty excited if this is a beat that Maya is on regularly here.
Thanks! I really like writing about the ways that sports intersect with economics (like this post) and politics, so hopefully I can contribute more on these topics in the future.
What a great first article.
Michael Lewis did a good podcast episode on this topic.
https://www.pushkin.fm/podcasts/against-the-rules/ref-you-suck
That's a top intersection for me too, so I'm looking forward to more.
Would be fun to hear Matt’s taking on the Bradley Beal trade -- although I’m not sure I’d believe anything short of “what an unlit it’s yes disaster.”
https://twitter.com/mattyglesias/status/1670539131225554945
"RAPTOR says that Paul is still better than Beal straight-up."
"Yeah, I mean at Beal's salary he seems worth less than zero" (in reply to "Yeah the Suns are making a mistake. Biggest problem is that Beal’s contract is just way way too big")
Matt used to engage in fairly frequent basketball blogging back in the day. It's good that his operation's expansion allows for diverse expertise. I agree—informative article. And belated welcome to Maya Bodnick.
Thank you!
It's nice to have some out-references to UK topics like Soccer (or, Football, as I would natively call it. Or 'the footie').
There's a good 'long read' from the Guardian as this relates to UK Soccer which more-or-less says that the home-team advantage and underdog-bias (though it's a bit more nuanced than that) are the game and refereeing 'working as intended' or maybe 'the way the game is meant to be played' (unlike the 'superstar bias' these would not provide any particular team with an overall advantage). Of course the rules-as-written implicitly include any difficulty or bias in enforcement, and were arrived at because they produced an entertaining and profitable sport.
https://www.theguardian.com/football/2023/mar/21/inside-world-premier-league-football-referees-pgmol-howard-webb-andre-marriner-darren-england
A really excellent article from the Guardian! And there’s a lot there even for those (like me) who only referee kids.
Super interesting. I didn't dig into football as much although there's LOTS of literature on it, but it's my impression that football officiating has not gotten much better (as NBA reffing has). I wonder why this is the case and also if online scrutiny has had an impact.
Thank you!
To quote from the Guardian article: 'Once, when Rosetti experimented with using VAR to review every incident in a single match, he found seven penalties and three red cards, according to a strict reading of the laws of the game. “But this is not football,” he said.'
That is to say, the rules as written are not and never were intended to be enforced by 'the eye of God', but rather by fallible and biased human beings.
Strictly rules-compliant officiating would not be 'better' - it would create an entirely different game from the profitable and enjoyable one that currently exists. The goal (heh) seems to be to reduce specific incidences of extreme public controversy using VAR (Video Assistant Refereeing).
Of course the game has evolved and will continue to evolve as sometimes-surprising technologies are deployed, but evolution is the key - popular and profitable changes will be kept, unpopular and unprofitable ones will disappear. Here's another Guardian article all about pitches and groundskeeping, for example:
https://www.theguardian.com/football/2021/jun/15/silicon-valley-of-turf-uk-perfect-football-pitch
Football is a difficult sport to officiate because there are tons of judgment calls (pass interference, holding, and roughing the passer being the most notorious) and also has calls that depend on viewing multiple attributes of the play ("completing the process of the catch" has been a particularly vigorous discussion of this).
There's another big, and obvious, difference between soccer and basketball: the amount of scoring opportunities. If a ref messes up a penalty or handball even in the middle of the first half, it could very well impact the outcome - it's hard (but not impossible) for any single refereeing error to sway the outcome in a basketball game, especially now the the NBA has the automatic review in the final two minutes of the game.
I loved the stats across different sports. The most amazing thing is that the home field advantage appears smallest in baseball. In baseball, unlike other sports, the rules literally favor the home team (batting last lets you know if you need one or more runs and to adjust tactics accordingly). Baseball also has non-standard fields which allows for (1) local knowledge of unique aspects, and (2) tailoring a team with character that best fit the park.
In baseball, the weakest major league team can beat the world series champion 25 or 30 percent of the time. Homs friend advantage appears small because most games are closer to 50/50 propositions than in other major sports
I'm not sure how that would work. I would expect if the base rate for "who wins in a fairly adjudicated game" were closer to 50/50, then the impact of slight biases on win rates would be greater, not smaller, because there are fewer other sources of variance. And I'd expect that if some teams are dramatically better than others, then when the better teams play away games, it would take truly blatant bias to make them lose when they would have otherwise one.
I think the reason is essentially unbiased officiating. If NBA home field advantage is largely driven by biased officiating, its reasonable to expect little home field advantage to be caused by less bias. Baseball has far fewer pure judgement calls then other sports. What meets the threshold of a foul is far more subjective than was a pitch in the strike zone or was the tag applied prior to the runner touching the base. By far the most important officiating in baseball is ball-strike calls, and basically since 2000, the MLB has tracked every pitch and told its umpires which pitches were misses. Only the best ball-strike callers ever make it to the majors to begin with.
Haha, I actually wrote another comment saying this same thing about hockey, which like baseball also has rules that favor the home team, and which also has a surprisingly small home team advantage (it's also a notably extremely fast-paced game so I'm not sure Jasper's slow pace explanation makes sense!)
To me the weaker home field advantage feels intuitive in baseball, because the slower pace of the game renders the crowd less impactful (they're also further from the action than in basketball), and the fundamental officiating activity—calling balls and strikes—likewise (to me at least) seems far less susceptible to home crowd effects than the officiating duties of North America's other professional sports leagues.
IDK if anything calling balls and strikes seems like it could be quite susceptible to this seeing as the home crowd boos for any pitch that goes against them, no matter how close it is and on actually borderline pitches umps could very well succumb. I think the officiation of balls and strike has less bias than in other sports because they aren't judgement calls (in theory). There is a strike zone defined by MLB which they can track very precisely. Plate umpires receive reports of their misses after every game and only the best ball-strike callers ever make it to the majors. I wouldn't be surprised if other types of calls in the MLB (tag plays, check swings, etc.) showed far more bias because of their less precise nature.
Referee bias sounds like it was great for fans for the same reason it was great for the NBA, and it only became not great when they were given the tools to know about it.
Now they fixed it and everyone is worse off. Absolutely fair games aren’t really beneficial overall.
It's corrosive. I'm not a fan of any of the teams, but I'll always remember when the Trailblazers with Scottie Pippen and the Kings with Chris Webber seemed obviously robbed by the refs in deciding playoff games against the Lakers.
There's probably a reasonable balance. Even though I describe ref bias decreasing, it definitely hasn't completely subsided. Where we are now seems pretty good bc it's gotten a lot less egregious while maintaining some judgement that improves the experience of watching games.
Perhaps if the refs did actually call a foul every single play, the players would adjust accordingly.
At first, perhaps (with a lot of missed free throws from Shaq), but I suspect players and coaches could figure something out eventually.
Yeah, the game was way more physical in the past with centers dominating by scoring inside the paint. Now the NBA's dominant center has the skill set of a point guard. Even average centers now have to shoot and defend further from the basket, even beyond the 3 point line.
100%. That was the turning point.
Put me on team "Then they should do that, for everyone in every game, and force a rule change to fix the problem."
Yes, this was my feeling as well. This article does a much better job explaining why the bias exists and what it's worth in points terms than it does in establishing the fundamental question of why the bias is a problem in the first place.
The curse of accuracy is very visible in soccer as well, where VAR calls now lead to goals being disallowed for reasons like the attacker's knee being a fraction of a centimetre past the defender, when previously goals like that would have been allowed to stand and people would have been able to celebrate rather than wait for a computer decision. It's not at all clear that fans are better off.
Sounds like you take issue with the offside rule moreso than its enforcement.
The flip side of offside decisions disallowing close but technically illegal goals is goals being disallowed for being offside when in reality they were onside, which happened a lot more in the past.
Overall offside VAR is good for the game, because enforcing the offside rule correctly without tech is pretty much impossible. Close offside calls involve the linesman hearing the ball being kicked and then judging the movement of the most explosive players in the world and keeping track of their arms and legs, and keeping track of one or more opposing players, all at the same time. It's impossible for their perception to be so fine to do that correctly, and IMO those calls used to pretty much be coin flips before VAR.
VAR has made more judgement-oriented calls arguably worse, because in the past the referee could always claim they missed something or had their view blocked or didn't see a foul in perfect detail. Now, if they make a call that differs slightly from a previous call or even one made by a different referee in another match, they are IMO much more under the microscope and can't get away.
Tight enough offsides are still judgement calls, they're just made in a booth far away. The precise moment the ball stopped contacting the assister's foot is hard to measure.
The presumption should be in favour of allowing goals with only visibly clear offsides brought back; if it can't be seen by the naked eye it shouldn't be offside. There's nothing worse than being in a ground watching a game and not celebrating a goal because defenders complain about anything at all and then VAR look for reasons to rule it out.
Then you get into the question of what a "visibly clear" offside is. And with needing to track the ball and so many players moving so quickly, even if you go with a really lenient standard like that, you're going to get missed calls where the offside player was half a body in front of their opponent (clearly against the rule), and calls where a player in full sprint is just onside a player not moving, but to the naked eye still looks offside.
I agree the delay in decision-making takes away from the fan experience, but so does being the victim of a blown call (and to my knowledge, England fans have been complaining for longer about being robbed by the ref in Germany in the 2010 World Cup (or Irish fans about Thierry Henry's hand of God) than they have any drawn out VAR call.
I think that the sensors inside the balls during the last World Cup could accurately capture the moment the ball was touched. I remember that particularly from that game where people were trying to figure out if a goal should be awarded to Cristiano Ronaldo or not, and I think the sensors said that he hadn't actually touched the ball (that was going in anyway). I expect that such balls will be used in more and more games in the years to come. And I also think that the offside line was automatically drawn by computers too.
Offsides should only apply within the penalty area (kind of like ice hockey). Let players bomb the ball into the corners.
On soccer, the offsides rule needs to be reformed. It shouldn’t be ok to simply wait in your opponent’s penalty area for a long ball. That would be too easy. However, once a team has worked the ball into scoring position, offsides is a silly distraction.
A rule that “offsides shall not be called based on a pass that began within 22 yards (the top of the penalty arc) of the opponent’s goal line” would be a huge improvement and would create more scoring
I always wonder why soccer can't just install a blue line like hockey does, so it's always clear where the offside line is.
The offside line in soccer moves with the last defender (technically the second to last player) all the time though. You mean a moving line for TV?
No, I mean a physical line on the field--something like extending the front line of the penalty kick box, or further back if appropriate. A moving line on TV would be good for viewers, but not helpful for players and officials. Maybe technology could some day find a way to put the moving line on the field without being distracting, though!
An actual line on the field that moves in real-time would be a very impressive achievement indeed. (It wouldn't solve everything though, as you actually need a moving plane, not just a line on the ground. Something like this: https://a2.espncdn.com/combiner/i?img=%2Fphoto%2F2022%2F0630%2Fr1030842_2_1296x729_16%2D9.png&w=1140&cquality=40&format=jpg)
I believe the nasl tried this a few decades ago. It wasn't much liked
Why?
Offside calls from corners are the least fun thing ever and I desperately want them eliminated
I indeed don't like having to wait to celebrate a goal, and I don't like millimeter offside goals either. However, I think this problem can be solved while keeping the VAR by increasing the thickness of the lines, and I hope that we'll eventually go there.
This is a valid perspective. I think there were a lot of forces supporting ref bias -- ref psychology, league profits, and (often) the enjoyment of fans. You're right that these biases profited the NBA because they usually made games more fun for fans:
-As a hometown fan, you want your team to win more at home b/c it makes it more desirable to go see games in person
-Most people like to see stars have amazing games
-Close games/series are also fun
With that said, I think there is a strong argument for fair officiating. It's great when the game is a spectacle and aligns with what I want to see as a viewer, but at the end of the day, I want the team that played better to win. When League credibility around this is really low, it actually does harm viewership/fan enjoyment. Just look to how sports like professional wrestling which are very skewed get much less viewership b/c it doesn't feel like a fair competition. NBA Twitter has blown the lid off of this problem and forced the NBA to readjust its profit calculus to make games more fair. Does that have downsides? Yes. But in the long term, fairness makes for better games.
I think an "ideal" outcome would be something like
1) Substantial bias for the home team and the underdog, but
2) When the game is close, bias goes to zero
So games are likely to be competitive but the final minutes are generally fair.
I agree that the most corrosive bias is when calls influence the end of games. Good news on this is that bias tends to decrease in the 4th quarter, although a close game bias persists (https://papers.ssrn.com/sol3/papers.cfm?abstract_id=1377964). I am super happy with the League introducing the Last Two Minutes report b/c I think this creates some important transparency around high stakes calls that can swing the outcome of a game.
I'm not wild about placing extra emphasis on the end of the game, because bad calls early in the game can badly influence future actions later in the game. Probably less so for a frequent scoring game like basketball, but more so for less frequent scoring games like soccer, hockey, or football.
Yeah. Even though bias declines at the end, if the 2 point avg. advantage to home court teams was given in the first 3 quarters, the damage is already done! A lot of people in the comments have been defending bias, but I think at the end of the day when it's transparently exposed it's basically indefensible -- both on principle and from a viewership-enjoyment perspective. I value fairness, and I know a lot of people agree with me. Just look at how incensed NBA Twitter is 24/7 about calls they view as biased. The League benefits a lot from looking credible and fair.
Agreed.
Or maybe just make the most correct, unbiased calls you can in all cases.
That would get you the fairest result but also fewer close games and likely fewer fans. Depends what you're optimizing for.
At some point, unfairness makes sports leagues lose fans -- like the fact that everyone knows professional wrestling is super biased. I think NBA ref bias is less stomachable in the age of NBA Twitter and lots of data access, bc it's harder to just look the other way. There's precise video clips and data analysis revealing this bias. For example, with home bias, it used to be easy to dismiss it as due to travel, scheduling, etc. But now the data has definitively shown that ref bias is the cause. Can we really tolerate these biases now that they're out in the open, as opposed to a period of more blissful ignorance and speculation? I think the NBA has concluded that bias is a problem and will cut into profits unless it's resolved.
I’m less familiar with basketball, but I wonder what they could do to make games more competitive without violating the fairness issue and thus losing faith of fans?
If you want to optimize for close games, then change the rules to make games closer.
I wonder if this would be seen as a more fair way to create this outcome than biased officiating. Probably (bc it's uniform), but I still think fans react to pointed rule changes like this. Case in point: the changes around the order of Playoff game locations and how this impacted the legnth of the Playoffs -- https://www.jstor.org/stable/40325820
I never got why people got so worked up over the 2-3-2 format.
I'm fine with that but I would imagine you have to be kind of subtle about it. If you just had a mercy rule at 10 points I don't think fans would like it.
The NFL seems to have managed this very well but the NBA's task seems much more difficult. But I'm not super knowledgable about basketball so maybe there's tons of options I'm not thinking of.
I love baseball and hockey, but I hate how that natural randomness plus large playoff fields leads to good teams losing short series early every year
I would optimize for the best athletes in the world being the ones to decide game outcomes.
Yeah I think that makes sense, my point is just that this doesn't necessarily translate into a super popular product so it probably will not be the north star for any pro sports league.
Yeah perfect is the enemy of the good here. It’s my belief (unpopular with my friends) that instant replay has been really bad for sports and sapped some of the fun out of them.
I was going to have this hot take but I see it's lukewarm at best.
I would not be surprised if increased sports gambling has an influence on public opinion. I'm sure the oddsmakers take referee bias into account but gamblers playing a spread would have different opinions of end-of-game free throws than home team fans would.
Glad to see someone is picking up the torch for fivethirtyeight. It wasn’t on my favorite subject, but the research and arguments were so compelling I read to the end.
We need to get a sports-related post from Maya each week.
It's like having 538 with the Slow Boring comments section. Definitely would support a weekly sports-themed post, even if it's just one of the brief open discussion posts and not a full article.
Should be seeing some mid-season baseball data covering the rule changes, for example.
Also Matt's sports opinions have been... somewhat more poorly informed relative to his average opinions about everything else. So if Maya is raising the bar, all the better!
Washington sports have been poorly PERformed relative to everything else so it's just statistically expected. (Yeah, yeah the Nats had 2019 but they've been bad recently. And Matt can't compete with Dara Lind on Nats fandom.)
Dan Snyder inflicted a generation of one of the worst sports performances in history.
"This Bodnick woman knows the game, 'Bron! She called us the Shaq and Kobe of the 2020s! The Michael Jordans of the present era!"
"Read it again, Steph: she said 2010s. Not 2020s. And not a typo."
"2010s? That's just...cold. Why do these young kids have to be so cold?"
"She knows the game, Steph. And I know when the game's over. It's over when you started complaining about the young kids outplaying you."
Outstanding introductory article, Maya!
One of the most frustrating things I deal with in interaction with fellow sports fans (interactions that are mostly positive, because people who watch sports are pretty great people overall) is the domination of conspiracy theory believing that goes on when a call doesn't go the way of the team they want to win. Far too many seem utterly convinced that there's some scheming puppeteering going on in the most upper annals of league executive offices to rig games for whatever fans believe is their sinister motive. This was an elegant way to explain how problems we see with officiating have a less sexier answer: they're humans that like any other are flawed, and let their flaws seep in when not checked and verified. I'm going to keep this article in mind when conspiracy theorizing is going on.
In addition to what you've added, two other thoughts as to how to continue to improve officiating:
--In the vein of another Slow Boring theme, automate as much officiating as possible. Some rules are heavily judgment calls where this might not be possible, but things like crossing an out of bounds or offside line, verifying 2 pointers vs 3 pointers, and so on, are clearer. Above all, I for one would welcome new strike zone overlords to baseball, and it would get rid of a lot of arguments in that game.
--Implement a sky judge as an additional check against biases officials on the field may have that can see the whole court from above, and also has the benefit of instant replay to look things over after the heat of the moment of play, and relay any feasible corrections down to the officials on the floor. This I think has the best potential in a sport like football, where there's regularly plenty of time after each play to review and digest what happened, and make corrections as appropriate.
I think psychological biases are the simplest explanation for ref bias, but it is a little suspicious to me that they align so well with NBA profits. Def not a proponent of "league is rigged" explanations, but I think historically there's probably been some subtle incentives for bias (i.e. what Price shows with regard to game assignments). Very important to soberly analyze this and not just allege conspiracy theories!
1) Love the automation idea. Tennis has started doing this pretty successfully I think.
2) How would a sky judge work? Would they be able to overrule refs on the court in real time?
Yeah, tennis is a sport where automation naturally works really well, lots of easy bright line calls in that sport.
With regard to overruling, this is something that happens all the time on the field when two officials may have seen something different, or are uncertain about what they saw and want a second opinion. They talk it over with each other, and quickly come to a collective conclusion about what to call. The sky judge just adds another official that's equal among all other officials in this ability--this official just has a different view from above and just needs to talk things over remotely.
I think it was simply inaction — the league being aware that the biases exist, but doing nothing about them (until recently) because they happen to align with incentives.
I’m still upset about just the number of foul calls overall. High-scoring games can be fun but things have swung too far in favor of offense. Let them play more, give defenders a chance, and do something about the calls that allow offensive players to bait defenders into shooting attempt fouls when they are not realistically in shooting position/have actual shots.
This video shows the change over the decades, it’s been extreme. Jimmy Butler got 3 FTs in the last game for kicking a defender…
https://youtu.be/6IPXSqOhykg
I agree with this sentiment in general, with one exception: I'd actually like to see the league tighten up the rules on defenders drawing charges. A lot of calls in favor of defenders look to my eyes like non-basketball plays. Like, there has to be way to reward a defensive player for legitimately getting into position and being willing to take a charge (aka penalize the offensive player for illegal contact). But the emphasis seems to have swung too far in favor of the "gotcha" play by the defender. Seems a bit gimmicky to me, and not in keeping with what this fluid game is supposed to be. Maybe more strongly define a time requirement for the defensive player to be planted, or consider changing size of the restricted area?
They should make the charge circle larger at the basket, but otherwise grant defenders the same right to their space as they do the player on offense.
"Make contact and wing the ball in the vague direction of the basket and hope for FTs" is super, duper annoying.
It’s certainly one of the main rule changes that swung things in favor of offense initially but I think it’s how it’s now combined with these other trends in favoring offense plus big-picture things like analytics people realizing 3s are the way to go that have just pushed everything too far in favor of O since it affords a lot of spacing for guys that can pull the trigger with ball in hand. I’m not saying I want the old days where a strong defender can just push an offensive player where they want to force them with hand checks, necessarily. Simply that rules always need to be reevaluated in context and it’s time to do something to rebalance. Do you’ve any particular takes on hand check or the topic broadly?
Just one quibble: you can’t compare changes in home team advantage in the playoffs without taking into account the relative strength of the two teams, because more games will be played on the court of the higher seed. The disparity in strength can vary by season because of differences in general competitiveness across the league. In a season where there are some very strong teams and below .500 teams are making the playoffs, the home court advantage will be larger than a season where teams are more evenly balanced
This issue is perhaps even more pronounced in college sports. Non-conference games are overwhelmingly held at the home field of the stronger team (e.g., in football, UNLV and Bowling Green play at Michigan this year; a Michigan/Bama/OSU would never travel to play those types of teams). That said, you can solve this problem by restricting your sample set to conference games, so perhaps these studies did that.
Also, ref bias is higher stakes in college MBB bc March Madness is single elimination. This makes you appreciate the 7 game series! Individual biases / bad calls matter less
Totally agree; I think some of the studies I looked at tried to adjust for team performance/strength but this is obviously really hard to do. Definitely gets at a broader issue around how hard it is to mitigate the enormous amount of potentially confounding variables around officiating.
Congrats on your first column. Nice work!
Having said that...
“The data is clear: referee bias is the number one cause of the home-court advantage.”
Whooooaaaaahhhh....slow down, Turbo! Sorry, but I don’t think you (or the research and stats you’ve cited) have in any way made this case.
I will absolutely concede that superstar bias is real (although as a Mavericks fan, I wonder how this works with superstar mega-whiners like our beloved Luka Doncic), but seems to me you’re totally dismissing other - more likely, in fact - possibilities that explain the home-court and come-from-behind advantages: that teams play harder and smarter for their own fans and they play harder and smarter when they’re trailing...
Why is it refs worry about getting screamed at by hostile hometown fans, but the same anti or pro hollering doesn’t impact the players themselves?
The idea that play shouldn’t vary because ‘arenas are standardized’ is baloney! What the hell foes standardized mean? This isn’t baseball - the court is the same, but sight lines, lighting, music, smells, altitude, locker rooms, arena logistics, security guards, parking lots...I admit that big American cities are homogenized, but - in the words of Robert Plant - never let’em tell you that they’re all the same. To me it is intuitive that any team playing 50% of games in a single venue and the other half scattered among 29 other barns will gain a level of comfort with the most frequent setting.
As for come-from-behind bias - isn’t a more likely explanation a simple reversion to the mean? The Kindergarten version is: teams fall behind because their opponent shoots unusually well, or because they shoot unusually poorly...but over the course of a game the hot teams cool and the cool teams heat up.
At any rate - basketball is a talkin’ sport, and I’m sure the discussion will be lively.
I think this is my key response from the article:
"Moskowitz and Wertheim found that this combination of disparities gave home teams an average of over 2.5 points per game and accounted for three-quarters of the home-court advantage in the 2000s. They also show that other commonly cited explanations — weariness from travel, unique arena characteristics that the home team is comfortable with, and unfavorable scheduling for the visitors — fall short. Visiting teams may be tired from travel, but home teams beat visiting teams at the same rate even when they are based in the same city and travel is marginal. And in the NBA, home teams don’t benefit significantly from unique arena characteristics because arenas are mostly standardized. Moskowitz and Wertheim do agree that scheduling is an important contributing factor to home-court advantage — road teams play more tiring back-to-back games than home teams do. But the authors conclude that this only accounted for one-quarter of the home team advantage in the 2000s... As you can see in this graph from FiveThirtyEight, home teams gained an average of almost two points per game when they played in front of crowds versus when they played in empty arenas. However, comparing free throw percentages at home vs. away helps separate these factors. If crowd cheers really encouraged the home team and boos really got to the heads of the visitors, we’d expect that teams would make more free throws at home. But during the 2020-2021 season, teams made free throws at very similar rates at home vs. away. In fact, many teams even shot better when they weren’t at home! It certainly seems that hometown crowd pressure does not have a huge impact on the players and that the crowd’s impact on referees is the true source of the home-court advantage."
Anyways, I totally hear you and a lot of people share your perspective! I think you should check out Scorecasting, the book I mention, bc they make a more persuasive case than I do for the dominant role of ref bias. I tried to summarize and substantive their key points here, but your objections make sense. There are so many different factors going into home court advantage that it can be hard to disentangle them. My impression is that ref bias is the #1 cause, but reasonable people can disagree.
She made this point pretty clearly, the stats show about 75 percent of home court advantage is attributable to referee behavior.
Well...she *asserted* that 75% referee attribution. That may be good enough for you, but I find the statistical reasoning entirely unconvincing.
No. Reread her article, she is citing other authors:
> Moskowitz and Wertheim found that this combination of disparities gave home teams an average of over 2.5 points per game and accounted for three-quarters of the home-court advantage in the 2000s.
If you have issue with the source paper fine but don’t say she just made this number up bc she didn’t.
I didn’t say she made the number up. I said she’s making assertions - based on the book and some papers - that I’m not buying. To make her point requires that we all completely swallow these sources’ conclusions - and I can’t get there with her.
It’s cool, Efm, we don’t have to agree!
You’re making a fool of yourself by giving her a hard time over something your wrong about.
After the college women’s final, the Athletic / NYT ran an article decrying foul calls on the star players. It does make the game less watchable and that article implies refs in men’s basketball know to go easy on superstars in big games. https://theathletic.com/4377949/2023/04/03/womens-basketball-officials-clark-reese/
That women's final was officiated so, so poorly. Not that LSU didn't deserve to win (they did!), but the refs kept making the game about themselves. Which, more than anything, is what fans object to.
I'm sure players were ready to kick out the refs and switch to street ball. It was intense even when it wasn't close.
This piece definitely contains some interesting information.
However, NBA refereeing is still in a place where many engaged fans view the games as being openly rigged. There are still refs who were involved in the gambling scandal that are refing. Scott Foster has the nickname "The Extender" because of the belief that the NBA deploys him to extend playoff series.
The point being is that the officiating in the NBA is bad to the point that conspiracy theories are pretty mainstream among fans.
One thing to note is that much of the piece focuses on bias officiating rather than just poor officiating. This makes sense because it is seems more possible from a data angle to see if something is bias than if it is simply a bad call.
Regarding the L2M report, in my experience these to little to quell fans anger or distrust of the refs. I believe the NBA says they review the whole game in a similar way but only release the 2 min version. It also allows the refs to appear more bias when they do things like apologize to the Lakers.
https://www.si.com/nba/lakers/news/nba-referees-issue-apology-for-missed-jayson-tatum-foul-ak1987
Also, I believe both Lebron and Curry actaully shoot very few fouls relative to their stature in the league. Curry possibly because of his shot selection, Lebron perhaps because of his size. These two are perhaps not the best example of people who get superstar calls. (Foul baiting aside, Embid, Luka, Giannis, Trae)
One interesting bias to look at might be size bias. I believe it was found in soccer that larger players were officiated more harshly but it a common complaint that big men are allow to be fouled quite hard without calls which sometimes encourages flopping, see Embid. Jokic being a pasty White makes it easy to see how beat up his arms are after games.
In the 2nd to last paragraph, "he NBA claimed that it hadn’t made any policy changes related to racism bias"
Is "racism bias" meant to be "racial bias"
1) I think fans will always complain about the refs, but I expect the complaints may decrease a little in coming years b/c bias has legitimately gone down. It's natural for there to be complaints but if the refs are mostly fair, that's not something for the League to worry about too much.
2) Interesting point on poor officiating; but that should come out in the L2M reports and general reviewing of data. I think the transparency from this + disciplining process are strong incentives for referees to clean up their act; the data has shown that this truly has been the case in recent years.
3) I read somewhere in my research that size bias wasn't statistically significant in the NBA, FWIW. Obviously there's some confounding factors there with star bias
Great article on a topic near and dear to my heart!
What a fantastic article!
Good article! I agree completely. I’m more of a baseball fan than basketball, but enjoy all sports. The increased transparency and accountability caused by improved broadcasting technologies and the internet have improved tall sports. For example, I love the “ump scorecard” on Twitter. Automation is the answer, where you can do it. They need to implement it wherever they can. VAR has made offsides calls in soccer almost completely objective. Baseball needs to follow suit with ball/strike calls. I’d love to see this level of transparency and accountability in our public and private institutions. It works. And, if you do it right, people will compete with each other to be the least biased and/or most compliant. Humans are naturally biased, but they also are naturally competitive. That’s why we love sports so much. Creating a fair playing field focuses our attention on competing.
VAR can help objectively determine whether a player is beyond the offside line, but it still relies on humans to decide where to draw the offside line. It can help objectively determine whether the ball struck a player's arm, but a human still needs to judge the player's intent. VAR doesn't make officiating more objective - all it does is shift the controversy from the officials on the field to someone sitting in a room somewhere.
Every TV replay I see does a very good job of defining the offside line.
As this is more of a political/policy Substack, if we think of the media as referees, what are some things we might expect to boost ratings due to more interest or as a result of natural root-for-the-underdog tendencies or wanting to be entertained/engaged? An incumbent President has a big advantage, so we might expect to see:
1. more emphasis on polls showing the President is in trouble due to negative favorability
2. emphasis on any poll showing a strong primary challenger to the President or movement in that direction
3. emphasis on polls showing the challenging party having a close race, or any move in that direction
4. more negative coverage of whoever is in the lead in every stage
5. a desire for more debates, and speculation about VPs and brokered convention scenarios, even though a VP has not been replaced since 1944, and before that, 1864, and we have not had a brokered convention in the primary election era (since 1970s)
Are there others, and does reality reflect this?