Thursday, November 4, 2010

Measuring Conference Strength - Offense

One of the big debates among the NCAA FBS football landscape is over how to adjust for different conferences. In other words, teams like Boise State or TCU are discounted due to the perception that they play in a conference that is weaker than teams that automatically qualify for a BCS bowl. So the first question is, is that true? And the second question is if it is true, how much of a discount should be placed on the conference?

Now the NCAA FBS production model includes conference fixed effects - which is a fancy way of saying the I control for teams in the same conference and thus control for teams in different conferences when calculating offensive and defensive productivity. But even since that happens, not all conferences are equal, right. Right!

Let me first explain how I calculated conference strength for the offense. After I calculated the offensive total productivity (model will be blogged about in the coming weeks), I added the total productivity of each school in each conference, which gives me total conference offensive production. Given that not every conference has the same number of teams, I then divided the total conference offensive production by the number of schools to get the average conference offensive production.

Once that is done, I took the conference that had the highest average conference offensive production and divided each conference by the largest average conference offensive production to get a number that would be between zero and one. On the offensive side, the higher the average conference number the more productive is that conference. Thus if a conference has an average conference offensive production equal to 0.90, then I conclude that conference is 90% as productive as the best conference. The conference with the highest average conference offensive production will always be 1.00 or 100%.

Calculation Summary (for Offense):
1. Add all the offensive production number for each team in a given conference which I call Total Conference Offensive Production.
2. Divide Total Conference Offensive Production by the number of teams in their conference, which I call Average Conference Offensive Production.
3. Rank Average Conference Offensive Production from largest to smallest.
4. Divide each conference by the largest Average Conference Offensive Production, which is the Percentage Conference Offensive Production.

So here are the conference strengths for the offense as of October 30, 2010.

Conference
Percentage
Big 10
1.000
Pac 10
0.981
Independent
0.976
Big 12
0.941
SEC
0.933
WAC
0.875
ACC
0.813
CUSA
0.804
Big East
0.753
Mountain West
0.752
Mid American
0.664
Sun Belt
0.629