I was going to comment on this post at The Big Lead yesterday, but let it slide. Since The Wiz has brought it up favorably today, though, I thought I’d make one point about a conclusion the author reached there.
Here’s the passage in question:
… Of course, then you get into the argument that before the BCS, the bowls would not always result in a consensus national champion. That’s when the playoff argument comes into play. Which is why I took the liberty of averaging the margins of victory for the Division I-A national championship games of the last 10 (BCS) years and comparing it to the average of the margins of victory of all the Division I-AA national championship games (from 1978). The results: Average margin of victory for D I-A championship games: 14.50 points. Average margin of victory for D I-AA championship games: 12.87 points. Just goes to show that if you want the best chance of having the truly best teams play for the championship, have a playoff. It’s better for everyone and everything…
Well, wait a minute here. He’s comparing 30 years of data against 10 years of data to make his argument. What’s the result if you compare identical time periods?
Based on his point spread chart…
… the average margin of victory in 1-AA title games over the last ten years is 17.0. If I’m not mistaken, that’s actually greater than 14.50.
Now I’m not a statistician, so I have no idea whether a ten year sample (or a thirty year sample, for that matter) is statistically significant. What I do know is that when you start juggling numbers to justify an agenda, you’re heading into Mark Twain territory.