Statistician detects refs' home bias DAVE FESCHUK In Game 6 of the NBA's 2002 Western Conference final, the Los Angeles Lakers, playing on home court, shot 27 free throws in the fourth quarter. The Sacramento Kings, throwing up their hands in disbelief at the one-sided officiating, shot 25 free throws for the entire game. The Lakers won that game, then won the series. In a flurry of outrage, conspiracy theorists from Dallas Mavericks owner Mark Cuban to former U.S. presidential candidate Ralph Nader called for a review of the league's officials. And an old basketball axiom — home team gets the calls — proved itself as a cliché that rings true. According to numbers compiled by a Florida economist, the Kings are far from the only victim of the NBA zebras' home-team bias. "I do think there's a tendency for certain officials to call more fouls on the visiting team," says Ted Kury, a Buffalo-born, Jacksonville-based economist who crunches NBA numbers as a hobby. "In statistics, you're never 100 per cent sure of anything, but I think these results are pretty clean." According to Kury's research, for instance, when third-year ref Derrick Collins has been in the building this season, the visitors have been whistled for about 2.8 more fouls per game than the home team. When 20-year veteran Eddie F. Rush has been working, the visitors have been hit with 2.5 more fouls per outing than their opponent. As for Gary Benson, the 16-year veteran, his games have seen the visitors charged with 2.3 more fouls than the home squad. League-wide, visiting teams were being whistled for about an additional half a foul per game through Monday's slate. Kury acknowledges there are limitations to his methodology. Because statistics for individual referees are unavailable, he only has access to the number of fouls called by the three-ref crews that work each game. But since the crews change frequently — and since Kury has been keeping track of these things for more than two seasons — undeniable patterns have emerged. Collins, Rush and Benson, among others, have been showing a home-team bias both this season and last. And what further convinces Kury that he's on to something is that the referees who are generally acknowledged as the league's best betray no statistical bias. Joe Crawford, the 28-year veteran who has refereed a record 201 playoff games, has been a part of crews that have called virtually the same number of fouls on the home team as on the visitors in each of the past two seasons. The same goes for 20-year man Dan Crawford, who is thought by many to be the cream of the profession. Kury says referee Steve Javie's reputation as a not-to-be-messed-with hothead is justified; this season the games Javie has worked have featured a third more technical fouls than the average. "In Javie's case, now we're seeing two years' worth of data, so if he is just at the wrong place at the wrong time he is extraordinarily unlucky," Kury says. The referees are under unprecedented scrutiny. In the off-season, the league hired a consulting firm to review the officiating and, as a result, this season is the first in which virtually every game is being attended by an observer who charts and rates every call by every referee. Last week, third-year referee Michael Henderson was suspended three games after he was a part of a crew that missed a crucial call in a Lakers-Nuggets game. The call went against the Nuggets. The Lakers won the game. The conspiracy theorists raged again. Henderson's suspension was unjustified. He was the junior man, after all, on a crew that included Jess Kersey and Jack Nies, who share a combined 51 years experience on the job. Still, it's heartening to see the NBA actually paying attention, however ham-handedly, to the performance of its referees. Kury has been paying attention for a while and he isn't impressed. "I'm a basketball fan, so you like to know that the best team wins," he says. "But what we're seeing here is there's not always a level playing field." Statistician detects refs' home bias Among the many, many serious problems with current NBA officiating.
Isn't it possible that since home teams win the majority of the time that the numbers are skewed because the visitors have to foul late in order to try to catch up?
Chicken and egg supposition. Especially given the fact that the reason most cited for home team superiority IS the preferential ref treatment.
Interesting article. It wasn't true last night when the refs blew countless obvious fouls b/c they didn't want to foul Shaq out.
I would be much more interested on a study of Laker bias or star calls. The home team getting one extra call every two games is not that significant.
Agree. Since the "conspiracy theorists" are suspecting a Laker biased, they should do a statistical study focusing on Laker games.
This is possible, but the analysis is not how many more fouls called on the home team or away team in general, but how many when certain refs work the game and why that number is not within the average (or a standard deviation or whatever) for games as a whole. Then you have to start asking you rself is it random or is there something else going on.
Analyzing if the home team gets preferential treatment is not very interesting because every team plays the same number of home games. If it is only a home bias, than the playing field is still level -- you give up a little on road games and get it back in home games. It may even be in fans' the league's interest to do it this way. What we need the statistics to show is whether certain teams or certain players are getting special treatment. Of course, you can't do this as an amateur because some teams may be more prone to fouling; some players may force more fouls. The answer lies with the group the league hired to monitor refs. Unfortunately, they likely won't publish their conclusions.
I agree completely. Having played a lot of basketball (duh, no not pro), I thought this was common knowledge. The home team gets more calls; I've always marked it down to some sort of deep-rooted psychological effect. At some level, it's very difficult to not want to make the fans happy. Along those lines, I think the margin of a half foul on average is surprisingly small.
We have been disagreeing more than usual lately. It is a truism that refs are affected by more than the rule book. That there is now data to prove same is, IMO, the first and important step required to bringing ref control of games back down to earth.
Nothing intentional, MacB. I like your threads, and this issue is important. I'm not able to watch enough games these days to see the actual data with my own eyes. I was surprised though that the average was one-half of a foul difference.
Very interesting. I wonder if the testers considered scheduling. When you're tired, you play lazier defense. So you foul more. If you're playing your third road game in 4 nights, you'd be more tired. More fouls. But I don't think being tired leads to 3 more fouls a night, either. This tests' results point to a homecourt bias, for sure, but probably not as pronounced as it appears.
Not sure of the relevance, but Denver was the home team in the Lakers' game in which Henderson was suspended.
Ohhh....and the Rockets were whistled for 27 personals compared to the visiting Lakers' 23 two nights ago. Hmmmm......
Shaq also shot something like 2-13 from the line. Something tells me some of those fouls might have been intentional.
There is a serious flaw in using statistics to determine fair officiating. Calling the fouls evenly on both teams isn't necessarily fair. What if one team is actually fouling more than the other team? Then they should be called for more fouls than the other team. Personally, I don't want to see an even # of fouls called for both teams consistently -- this just indicates (to me) that the refs are consciously playing the numbers game (to make it look like they're fair) and not really calling what they see. Is this really fair? Is it really good officiating? I don't think so. I'm pretty sure that good coaches are aware of how the ref's call the games. Pat Riley used it to his advantage. He knew the refs couldn't call games too unevenly, so he coached his players to be more rough and physical knowing that the refs couldn't call every foul. The only way the refs can be truly fair is to call what they see. Maybe it would get rid of ugly thug-style basketball.
