My favorite part of sports might be the fan atmosphere. In literally any competitive environment, an electrifying crowd can make great moments even greater. Whether it’s basketball, football, baseball, or soccer, the deafening roar of devoted fans never gets old. These fans are willing to put their vocal cords on the line in order to provide a boost to their favorite team.
The phenomenon of home-court (or field) advantage is well-documented in sports. Teams and players tend to perform better while playing at their own venue. Conversely, their performance generally declines when forced to travel to an opposing team’s stadium. That’s one reason why possessing a high playoff seed is so valuable — the slight advantage of playing at home can make the difference in professional sports.
So, why does it exist? There are plenty of different reasons which could explain it. Referees are imperfect, so it would make sense for them to be slightly influenced by the loud grievances of 20,000 fans. The effect that traveling long distances has on the human body can also impact a professional athlete’s performance. Many people believe there might even be a psychological component to the matter. The self-fulfilling prophecy refers to the event where a person expects something to happen, so they internalize this expectation and align their behaviors. Maybe playing at home isn’t that important but because it’s talked about so much that it has a psychological effect on players.
Well, whatever the reason for home advantage is, it certainly exists. In the most recent NBA regular season, the home team won 59.3% of games. So, we clearly know that many players must be impacted by this phenomenon. But to what extent? Also, are there players who aren’t impacted? Do some players actually play better on the road? Let’s find out.
The players above the y = x line shoot the ball at a more efficient rate at home, while the players below the line appear to benefit from playing in enemy territory. Players close to the line (like Stephen Curry) experienced little to no impact from the venue which they are playing at.
Unsurprisingly, most players find themselves above the curve because most players perform better at home. Not all of them, though.
Thomas Bryant benefited the most from being surrounded by supportive fans in 2019, while Jonathan Isaac exhibited the greatest boost in efficiency while playing on the road. Meanwhile, the greatest shooter of all-time appeared to be impervious to the phenomenon of home-court advantage. Maybe that’s part of the reason he’s … well … the greatest shooter of all-time.
There’s one unavoidable question left to tackle: are these results consistent?
I went back and tracked the past five seasons in order to see if we’d get some similar results.
Once again, most of the points on the graph are situated above the y = x line. Over the past five years, NBA players have tended to shoot the ball at a more efficient rate. When playing at their home-court, Nerlens Noel exhibited the most significant efficiency surge, while Robin Lopez suffered the largest hit to his efficiency. meanwhile, Rudy Gay’s eFG% at home (50.87%) is virtually indistinguishable from his eFG% on the road (50.85%) through this five-year span.
Some of the points you may have observed in the previous graph of a one-year sample stay consistent in this representation of a five-year sample. For example, on both graphs Nuggets teammates Paul Millsap and Jamal Murray are in close proximity and are situated far above the curve (not a team I’m surprised to see). D.J. Augustin and Danny Green both experienced a significant boost in efficiency while playing at their home court in both samples. On the other side, Ricky Rubio maintained his position below the curve, solidifying his new title as a player who underperforms at home.
While there are some similarities, there are also plenty of inconsistencies. There are multiple players who had extremely variable home-court efficiency boosts through this five-year span. For instance, Kentavious Caldwell-Pope had two seasons where he played far better on the road, two seasons where he played far better at home, and one season where his performance stayed consistent regardless of venue. He only switched teams once through the duration of this sample.
For whatever reason, home-court advantage in the NBA affects different players in different ways.