Before the season begins, we want to share and explain some of the statistics we will be using in our game previews and reviews.

Totals- Total points and yards function as a collection of everything that happened within a game. Obviously important, but as an aggregate it hides some of the meaning within its all-encompassing nature. It tells you which teams are producing, but it doesn't tell you why or how it happened, and it lacks context.

Yards Per Play (Y/P)- Y/P works both offensively and defensively, and it measures the average number of yards a team gains per play,  or in the case of a defense, the average number that it gives up per play. Y/P can be further broken down into Yards Per Rush (Y/R), Yards Per Catch (Y/C), and Yards Per Attempt (Y/A.)

An interesting anomaly regarding yards per play: Ohio State (6.3) significantly outgained LSU (4.2) in Y/P during the 2008 BCS National Championship game, but poor third down efficiency (23%) and a negative turnover margin (-2) limited the offenses' effectiveness.

The average Y/P for the national champion team has been 6.3 over the past ten years.

Mean figures- Yards per statistics do not reveal everything, as a player can have a number of negative carries with one big run skewing the statistics in a certain direction. Mean figures can give you an idea of where the bulk of the carries, passes, or catches are clustered.

Points Per Game (PPG)- Pretty self-explanatory; it's the average number of points a team scores , or gives up, per game. There are various filters that one can apply to make this more meaningful (i.e. filtering for BCS competition only.)

Turnover Margin- Turnovers alter possessions, and possessions provide control. In football, the ball is life, and losing control of the ball is like giving away years of your life.

No national champion has had a turnover margin worse than +5, and the average has been +14.2 over the last ten years.  Championship teams win the turnover battle.

Tackles For Loss (T.F.L)- measures a defense's ability to penetrate and cause negative yardage against an offense; when flipped, it measures an offense's ability to avoid negative plays. It does not include sacks.

Negative Play Percentage (N.P.P.)- tackles for loss allowed + sacks allowed divided by the total number of offensive snaps a team takes.  I created it to gauge how many negative plays an offense has, which, theoretically, means it acts as a referendum on the offensive line. It can also be flipped to measure a defenses' ability to cause negative plays.

Success Rate- A percentage measure originally created in the book The Hidden Game of Football. It measures the percentage of plays that can be considered successful, based on this definition of success:

50% of needed yards on first down, i.e. 5 yards on 1^st and 10 (altered from 40

% for college.)

 70% of needed yards on second down, i.e. 3 ½ yards on 2^nd and 5.

 100% of needed yards on third or fourth down, i.e. 1 ½ yards on 3^rd down.

The average success rate, for each down, hovers between 41% and 45%.

Jim Tressel has been using Success Rate since his time at Youngstown State. Ohio State partially measures their offensive success utilizing this statistic; they even break it down by situation (field position, quarter, opponent, etc.) and scheme (formation, personnel, play.) The following image is a brief look at Coach Tressel's take on the stat, from a lecture he gave early in his Ohio State career:

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