by Ken Pomeroy on Friday, December 17, 2010
Question - when Texas A&M beat Washington 63-62 in College Station last Saturday, were you convinced that the Aggies were the better team? If you are like most fans and media members, you were. However, if anything, that result proved the opposite.
Fortunately, there are plenty of rematches in the sport, so one can use real data to determine how much a head-to-head victory is a true verdict of superiority. Last season, there were 1,049 regular-season conference games which were a rematch of an earlier game. The winners of the initial game won 61.1% of the rematches. Not exactly a figure that inspires confidence that the outcome of a single game is useful to compare two teams. Keep that in mind as you make arguments about one team being better than another.
We should break this down further, though. Because we’re only looking at conference regular-season games in this sample, location is very important. For instance if the victor of the initial game was the road team, it won the rematch 80.2% of the time. This shouldn’t be surprising because it’s more difficult to win on the road and the rematch would be an easier game for the winner since it would occur at home.
The flip side is more instructive. When the home team was the winner of the first game, they were a collective 309-326 in the rematch. That’s right, a home winner is more likely to lose a rematch than win it. It gets better, though. A home team winning the first game by single-digits went a collective 96-195, winning 33.0% of the time. Considering that overall, road teams win conference games about 38% of the time, close home winners are really not proving their superiority at all.
Wait, there’s more. Home teams that won by one or two points were 16-52 in the rematches, winning just 23.5% of the time. Most fans like to think the results of a close game as just because teams that emerge victorious show grittiness, heart, and toughness. But those teams were almost certain losers when they faced the same team on the road. What happened to the grittiness then? To me, there’s no greater statement to the influence of luck in the outcome of a close game than the struggles of close home winners in a road game against the same team.
If you still doubt, consider this: The average margin for the winners of the first game in those cases was +1.6 points. The average margin for those teams in the rematch was -6.9, almost exactly double what many studies have shown to be typical home court advantage. Was there anything more going on for the close home winners than just simply being at home? It doesn’t appear that way.
There are a couple of things to take away from this - the outcome of a game is not enough if you insist on using head-to-head results for comparing two teams (which you totally shouldn’t, but that’s another article for some other week with sparse action). Site and scoring margin have to be considered as well. And be careful about thinking that Washington is worse than Texas A&M, because they’re probably not. Given home court advantage, that result is more evidence that Washington is very good.