On the relative importance of home field advantage

Clutch, streakiness, the hot hand effect. All are attempts to explain certain intangible aspects in all sports. Perhaps the most well known of these phenomena is home field advantage. Its existence is accepted as a near-universal fact, but should it be?

On Monday, I explored how the prospect of playing neutral site games down the final stretch of the season could benefit the Yankees more than any other team in baseball. The country-wide presence of Yankees fans can turn any neutral venue into a home field atmosphere. This got me thinking about home field advantage in general and how robust of an effect it exerts on the outcome of a game. Almost immediately, I fell down the rabbit hole of conflicting accounts as to the materiality versus fallacy of home field advantage.

Every year, Yankees fans clamor for the team to win down the stretch to secure home field advantage through the ALCS. Playing four games at home is posited as an absolute necessity, without which the Yankees have diminished chances of reaching the World Series. This made me wonder, what exactly is it about home field advantage that improves the performance of the home players?

The first thing that comes to mind are the psychological effects. Of these, the obvious component is the atmosphere created by the home fans. The roars for the home team and the jeers for the visitors creates an intimidating environment, but the extent to which this unbalances the away team is dubious at best. However, there are some measurable effect for the home team.

Studies have shown that defending home turf can raise testosterone levels, and adrenaline levels are certainly increased by home support. I also have to believe that a home team athlete might exert greater effort so as not to let home fans down. And then of course there is the placebo effect. Simply believing that you will do better because you are playing at home can actually confer a material improvement to your performance.

Comfort levels and familiarity could also come into play in contributing to home field advantage. The muscle-memory one develops in a home ballpark makes the split-second calculations that populate a ballgame much easier. Factors such as the speed of the infield, the outfield dimensions and proximity of the warning track, sight lines and depth perception, angles of walls, and caroms off of surfaces are all more automatic when playing in one’s home stadium. Throw in the comfort of sleeping in one’s own bed and it is clear to see how playing at home would be beneficial.

With all of these influences acting in concert, you might expect the home team to be nearly invincible. However, the data paints a more sobering picture. According to a 2017 study looking at results dating back to 2000, the home team in baseball won about 54% of the time in the regular season and in the playoffs. While the numbers would suggest that home field advantage does confer a slight edge, it is not nearly as dire a need to secure Championship Series home field as originally thought.

The same study did show that NBA home teams have their chance of winning increased by 14% during the playoffs. In addition to the massive importance of depth perception and its variation between venues, this could be down to the format of a basketball game.

We’ve all seen the stretches of multiple big plays in quick-fire succession that sends the home fans into a frenzy and forces the visitors to take a time out. Not only do the visitors have to expend that time out, but the hostile environment of the arena is in the most intimate proximity of the four major sports. In baseball, the long periods of inactivity in between short burst of action make it more difficult for the crowd to sustain a level of influence on par with basketball.

I was shocked to learn the realities behind home field advantage. Given the numbers, it may seem overrated relative to the uproar of supports demanding that teams go all out to secure playoff home field. Heck, the Yankees won the first game of the 2019 ALCS at Houston, and the proceeded to lose the first two games at Yankee Stadium. That being said, the Yankees should still try their hardest to win the most games in the regular season, if for no other reason than to give ticket holders an extra game come the playoffs.