Football is a funny game with an odd-shaped ball that take funny bounces and there are 22 players on the field of play on every snap – interpretation will always come into play when looking at football stats.
One stat especially subject to interpretation is the “Scoreability” index.
Ostensibly the scorebability stat measures how efficient your offense is. It is the number of yards your offense has to move the ball in order to score a point. However, to get the scoreability number, we divide the total number of yards of offense by the number of points scored by the team. What isn’t transparent here? The number of points scored by special teams or by the defense gets factored into points scored. For teams that score frequently on special teams or defense, the “scoreability” number inflates how efficient a team’s offense really is.
Look at the above chart of how the ACC performed in scoreability in 2008. The Tar Heels finished first in the ACC in scoreability, and turned in the 16th best scoreability number in the BCS over the past five years, and the seventh best number among BCS teams in 2008. Against BCS teams, however, North Carolina ranked 71st among all FBS teams in total offense. What is going on here?
North Carolina scored two touchdowns on punt returns and four touchdowns on interception returns in 2008. In 2006, UNC’s worst year in scoreability out of the last five, they returned no interceptions for touchdowns, and on punt and kickoff returns – again, no house calls.
Intertwined the whole concept of efficient offense in terms of scoring, there is a premium on the ability of special teams and defenses to put points on the board when it comes to the scoreability index. The reverse would also be true in bendability, in terms of not allowing special teams or defensive scores.
Which is why we see above that out of the 10 best scoreability marks of the past five years, Virginia Tech owns four of them. It also points out something we should know but often act as if we don’t – the scoreboard doesn’t care how the points got there.
If you’re looking for a place to help explain Maryland’s surprising success a year ago, look no further than this stat. Maryland returned two punt returns for touchdowns last year, while also housing four interceptions. As a result, they turned in the second best scoreability number in the ACC last year, and the 8th best number recorded by an ACC team in the past five years.
In terms of “stats that matter,” scoreability had the eighth highest correlation to winning of the 27 categories we studied, and if you exclude the differential stats (PPG differential, e.g.), it had the third-highest correlation to winning of the stats we looked at.
Tomorrow: Part IV, Turnover Margin