Home Court Advantage – Comparing Apples to Apples

It is not uncommon to hear or read about how much home court advantage a college sports team has, based on the team having won a high percentage of games played at home. In a recent article, “Home Court Advantage – Can You Believe All You Hear?” I addressed the issue of why this kind of analysis is flawed unless you compare percentage of home wins to percentage of away wins.

Here I am going to address a second reason why what often is mistaken to be home court advantage really isn’t. The issue is that the concept of home court advantage requires that one compare how well a team does at home with how well they do on the road, when the opponents under these two circumstances are of more or less equal ability.

Let me use a somewhat absurd hypothetical example to make my point. Imagine that a decent, but not outstanding, major college baseball team plays twenty games, ten at home and ten away. Continue to imagine, but I have to warn you that here it gets a little weird, that the ten home games are played against local high school JV teams, while the ten away games are against Texas Tech, Minnesota, Arizona State, Stanford, Florida State, Texas, and other perennial college baseball powerhouses. It’s not difficult to imagine what the results would be. The team would most likely win all ten of its home games and probably be extremely lucky to win even half of its away games.

So, since the team won a lot more at home than away should we conclude that they have a big home court advantage? Of course not. Its simple to see that they were playing the easy teams at home and the hard teams away. That’s why they did so much better at home.

Although the hypothetical example is kind of weird, in reality this same situation occurs every year in every major college baseball conference. Let me explain. Major college baseball teams play roughly half of their games against other teams in the conference in home-and-away series. The other half of their games are against non-conference opponents. When I analyzed all of the baseball games played by teams in the SEC, ACC, Pac-10, Big Ten, and Big 12 Conferences from 1998 through 2007, here’s what I found. These teams played most of the non-conference games at home and they won most of those games. In fact, against the “easy” non-conference opponents, they won about 79{b7ad85a4b69bcdc6d2a1761d785d8b301857dc9ffea60b5a6c87077e9295409b} of the time at home. Against conference teams (those of more similar ability) they won about 56{b7ad85a4b69bcdc6d2a1761d785d8b301857dc9ffea60b5a6c87077e9295409b} of the time at home.

From these analyses, it should be clear that the 79{b7ad85a4b69bcdc6d2a1761d785d8b301857dc9ffea60b5a6c87077e9295409b} figure is inflated due to a relatively easy non-conference home schedule. The 56{b7ad85a4b69bcdc6d2a1761d785d8b301857dc9ffea60b5a6c87077e9295409b} figure is a much more accurate indicator of home winning percentage because it was against teams of similar caliber within the conference.