For social scientists, the National Basketball Association isn’t simply a source of pulse-pounding excitement, it’s a laboratory that yields insights into human behavior. As the strike-shortened season settles into its groove, we examine some NBA-related studies that have dribbled out in recent months, exploring such game-changing factors as performance-sapping stress, unconscious racism, and the power of positive momentum.
Chokehold: LeBron Explained
Do world-class athletes choke under pressure? Evidence from the NBA suggests the answer is yes — but only during the final minute of very tight games. For a study published in the Journal of Sports Economics, researchers led by Oregon State University economist Zheng Cao analyzed free-throw data from the 2002-03 through the 2009-10 seasons. They found players “shoot on average 5 to 10 percentage points worse than normal in the final seconds of very close games.”
This tendency to choke occurs when a team is down by one or two points. It’s noticeable when one minute is left in the game and grows dramatically when the clock ticks down to 15 seconds. Interestingly, the researchers found no evidence of choking when the game was tied in the final 15 seconds. “In these situations,” they noted, “players may perceive that even if the shot is missed, the shooter cannot be held directly responsible for the game outcome.”
Choking does not increase during playoff games, and it isn’t significantly affected by whether the game is played at home or away. But personal performance history matters: Cao and his colleagues report that missing shots in high-stress situations “is more likely for players who are worse overall free throw shooters, and on the second shot of a pair after the first shot is missed.” Time pressure combines with a lack of confidence to feed performance-inhibiting anxiety.
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But the pressure to perform isn’t just a matter of the time left on the clock. Consider this familiar scenario: a highly regarded NBA player becomes a free agent and signs with a new team. The fans are thrilled. But when he puts on his new uniform and gets out on the court, his performance doesn’t live up to expectations. This maddening phenomenon was analyzed by German researcher Christian Deutscher in a 2011 study published in the Journal of Sports Economics.
He found that “players who changed teams due to free agency suffer a decline in free throw performance at home games, compared to those who stay with their old team or are traded.” This suggests that “social pressure” — a need to justify that huge contract they just received — “leads to a reduction of performance at home.” Their performance didn’t suffer during away games, more evidence that the problem is a perceived need to impress a new set of fans.
Momentum at the Charity Stripe
The opposite of choking is having a “hot hand” — having a higher probability of making the next shot if you just made a shot. Although many players and coaches firmly believe in the phenomenon, statistical evidence of its existence has been hard to find. But in a 2010 paper published in the Journal of Quantitative Analysis in Sports, Jeremy Arkes describes this using a sophisticated method of crunching the numbers to conclude that the hot hand “is a real phenomenon.”
Arkes’s data set was the 64,698 free throws taken during the NBA’s 2005-06 season. He writes that “hitting the prior free throw increases the probability of making a free throw by two to three percentage points,” adding that this tendency “appears to be stronger for frequent than for infrequent foul shooters.”
In a 2011 study published in the same journal, Arkes provides evidence that positive momentum also works on the team level. He looked at data from the NBA’s 2006-07 through 2008-09 seasons and developed a model that takes into account the quality of a team’s opponents over a string of three to five games. “After holding team strengths constant,” he writes, “greater success in the past few games leads to a higher probability of winning the next game. Likewise, poor play over the past few games leads to a lower probability of winning the next game.”
Arkes cautions that these results “are not necessarily applicable to other sports,” noting that baseball games are hugely influenced by the starting pitcher and that “football is more a game of physicality than a game of skill.”
Myth of the Urban Phenom
We’ve heard the story: young kid grows up in the ghetto and seems destined for a life of poverty, but when he gets onto the run-down local basketball court, he dazzles friends and onlookers alike. Word gets out, a scout takes notice, and soon he has signed a multimillion-dollar deal to play in the NBA.
This popular narrative is deeply misleading, according to a 2010 study published in the International Review for the Sociology of Sport. Joshua Kjerulf Dubrow and Jimi Adams examined 245 newspaper articles profiling 155 NBA players between 1994 and 2004. They found that 66 percent of black players, and 93 percent of their white teammates, grew up in either middle-class or upper-class households.
Looking at the data from the other direction, the researchers estimated that 34 percent of black NBA players, and 7 percent of white players, came from a “lower social class background” — that is, their family of origin was at or below 150 percent of the poverty line. For the population as a whole, 45 percent of young black men and 23 percent of young white men fall into that category.
It’s conceivable that the players whom journalists choose to profile aren’t representative of the league. But the researchers argue that, at the very least, these findings cast doubt on the notion that “for historically marginalized groups such as African American males, sport is a pathway to upward mobility.” It appears the advantages that come with growing up in a reasonably well off family also apply to young men seeking a career on the court.
Put Me, In Coach. I’m One of Us
Want a little extra playing time on the basketball court? It helps if you and your coach are of the same race. That’s the conclusion of a 2011 study published in the Journal of Sports Economics. Jesse Schroffel and Christopher Magee compared players of roughly equal skills and report that “having the same race as the coach increased playing time by between 45 and 55 seconds per game on average.”
The researchers looked at the 1995-96 through 2003-04 NBA seasons and found this particular form of favoritism was most evident in the late 1990s. They had guessed that this bias would be greater in time-pressure situations, as when a substitution is made during the course of a contest, but found that the tendency to favor a member of one’s own race was only “slightly stronger” under those conditions. “While obvious forms of discrimination in the NBA appear to have been minimized,” they conclude, “the literature has shown that more subtle discrimination has remained.”