When the Ottawa Senators traveled to New York to take on the Rangers in Game 6 on Tuesday night, it was fair to think the series would probably head back to Ottawa for a Game 7. The Senators got drubbed in the series’ first two contests in New York, and the nervously raucous Madison Square Garden crowd was hoping to give the Rangers a key home-ice edge in an otherwise tight series. The problem with this thinking, though, is that home-ice advantage is not much of an advantage in the NHL — and it has proven even less important in the playoffs.
And so, the Rangers’ 4-2 loss at home (and playoff elimination) provided just the latest in a string of home-ice disappointments this postseason. So far, home teams are exactly .500 (33-33) in 2017, their worst playoff showing since 2012, when teams actually had a losing record at home at 39-47. Hockey home-ice isn’t actually the disadvantage that record would imply, but it’s also not the game-changer we’re used to seeing in other sports like football and basketball, where home teams have been very spoiled over the years.
To measure the strength of each league’s home edge, I gathered data on every regular-season and playoff game since 2000, tracking how often the home team won. I also used our Elo ratings1 to calculate an “expected” winning percentage for each game — based on the quality of the two teams — had the matchup been staged at a neutral site. (This isn’t important for the regular season, because every team is scheduled for roughly equal home and road games. But in the playoffs, better teams are rewarded with more home games, a factor for which we must control.)
Comparing home teams’ actual winning percentages to what we’d expect on neutral ground, we can see how much of a boost teams get by being at home in each sport. We can also see how that boost changes from the regular season to the playoffs — if indeed there is a change.
The NBA and NFL have the biggest regular-season home advantages, improving a team’s chance of winning by 10 and 7 percentage points, respectively. And those benefits grow even larger in the playoffs, ballooning to as high as 14 percentage points for NBA teams. NFL home teams gain almost 5 extra points of win probability in the playoffs — again, after controlling for the fact that better teams tend to get more postseason home games.
In baseball and hockey, on the other hand, playing at home doesn’t get you nearly as much help. MLB teams win about 54 percent of home games whether it’s the postseason or not (so much for last licks!), and while NHL teams do a bit better at home in the regular season (55 percent), they actually see their advantage decrease slightly in the playoffs.
In general, home advantage is a subject that deserves more research, simply because we’re still not entirely sure what combination of factors actually cause it. Some, like crowd noise, are obvious, while others are written into the sport’s rules (home hockey teams have the right to make the final line change before the puck drops, giving them a consistent edge in matchups). Other phenomena, like the home team getting preferential treatment by officials, still need further study. But numbers like the ones in the table above show that each sport brings its own weird nuggets to the overall topic of home-field/court/ice.
Either way, after their loss Tuesday night, maybe the Rangers and their fans will take solace in being the latest case study for a fascinating natural experiment. (Probably not.)
