Tuesday, September 28, 2010

On Home Field Advantage

Over and over in the press I keep hearing about what a difficult place Qwest Field is to play. Being a season ticket holder, my impression is quite different. Sure, the atmosphere is fantastic and I love going to matches, but I never consider Qwest the fortress that some people like to make it out to be.

Home field advantage in soccer is almost taken as fact and is the reason behind the beloved away goals rule (the theory being that it is more difficult to score away from home so those goals should count more heavily). Stadiums with high attendences and rabid fans are seen as being more advantageous than smaller, quieter stadiums. Altitude is also seen as an advantage, so much so that FIFA tried to ban World Cup qualifiers played above a certain altitude.

Given these common perceptions of home field advantage, you'd expect to see MLS teams with high attendence (Seattle, Toronto, LA Galaxy) or high altitude stadiums (Real Salt Lake, Colorado) perform better at home than other teams in the league. Additionally, you'd expect good teams to perform above average both home and away and the converse for bad teams.

Specifically I'd expect to see:

  • LA Galaxy, Real Salt Lake do well both home and on the road, but better at home
  • Seattle, Colorado, Toronto do well at home but average on the road
  • Everyone else should perform equally on the home and on the road

Note, my definition of performing "well" at home is earning more points than the league average earned by the home team. Across the league, the home team earned approximately 0.8 points more per match than the away team. What do we actually see?

As expected Colorado and Toronto over perform at home. Surprisingly LA does better on the road than at home, but not surprisingly it does well in both situations. The big surprises were RSL and the Sounders. The Sounders are quite average at home while they are above average on the road. It's possible that the Sounders are a better team than their record reflects but is at a disadvantage because of the hype surrounding their stadium experience. Visiting teams frequently comment on how pumped up they were to play in front of so many fans, while the Sounders typically go through a period of lethargy in the first 30 minutes or so. Real Salt Lake, on the other hand, have a true fortress for a home field. They are a very average team on the road but near invincible at home. I'd expect them to do better at home, but I wasn't expecting them to be so average on the road. Things should be interesting come playoff time. If RSL can't improve their road form, look for an early exit from them.


  1. Are you controlling for weather?

    Also, the away goals rule stinks.

  2. I thought about controlling for weather but I haven't tracked that data down yet. This is just a superficial analysis to get me started. I think the next step is to figure out what the expected home/away breakdown per club would be rather than using the league average. Either way, RSL is dominant at home. Impressive!