Let’s welcome back our old friend, regression to the mean! Matt Melton returns with his annual conference yards per play analysis.
… Since 2005, I have collected YPP data for every conference. I use conference games only because teams play such divergent non-conference schedules and the teams within a conference tend to be of similar quality. By running a regression analysis between a team’s Net YPP (the difference between their Yards Per Play and Yards Per Play Allowed) and their conference winning percentage, we can see if Net YPP is a decent predictor of a team’s record. Spoiler alert. It is. For the statistically inclined, the correlation coefficient between a team’s Net YPP in conference play and their conference record is around .66. Since Net YPP is a solid predictor of a team’s conference record, we can use it to identify which teams had a significant disparity between their conference record as predicted by Net YPP and their actual conference record. I used a difference of .200 between predicted and actual winning percentage as the threshold for ‘significant’. Why .200? It is a little arbitrary, but .200 corresponds to a difference of 1.6 games over an eight game conference schedule and 1.8 games over a nine game one. Over or under-performing by more than a game and a half in a small sample seems significant to me. In the 2016 season, which teams in the SEC met this threshold? Here are SEC teams sorted by performance over what would be expected from their Net YPP numbers.
I’d like to get excited about some of this, namely the part about Florida overachieving, but looking back on last year’s analysis,
… the depressing truth may simply be that Jim McElwain is a good coach. Of course, maybe it just means the Gators are overdue to come back to earth.
On the other hand, those stats certainly give every indication that Bret Bielema may be the SEC’s most underrated coach. Take that for what it’s worth.
In any event, keeping Matt’s caution about the significance of over or under-performing by more than a game and a half in a small sample in mind, what’s particularly striking about the 2016 numbers is that a majority of conference schools posted variations under .100, and half were under .050. If I didn’t know any better, that looks to me like conference YPP was a pretty good measuring stick.