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Introducing Sabermetrics to the NFL

Sabremetrics have rapidly become a mainstay in the world of baseball.  VORP, WHIP, ERA+ and other statistics have been created to help shed light on what may not be easily seen through raw totals.  Major league front offices have quickly, and smartly, embraced this trend.  Many teams employ individuals who do nothing but sit behind closed doors crunching numbers trying to discover the metrics that most closely correlate with team success.

Football, meanwhile, has largely ignored this statistical shift.  There are some websites and individuals who have taken on the mammoth task of trying to discern both the quality of a player, and the impact that player makes on a team, through statistical means.  It is a very difficult process.  Unlike baseball, which in many ways is a series of separate individual matchups, football is a strongly team-oriented game.  On any given play, one player blowing an assignment will reflect poorly on the team as a whole even if the other 10 players are performing their duties perfectly.

But simply because a task is difficult, that does not make it not worth doing.  Rather than throw our collective hands up, curse and give up because the task seems impossible, we should investigate the matter a bit further.

Let's start with the building block -- passer rating.  It is a flawed place to begin, but at least it is something.  First some explanation of what the passer rating is, and is not.  It is a measure of how efficient a quarterback is when he throws the ball.  It is not a measure of how good a quarterback necessarily is.  Rushing ability, sack avoidance, leadership, and many other factors are left out of this calculation.   

However, there is some worth to it.

We can all agree that completing a higher percentage of passes is better than completing fewer, right?

We can also all agree that touchdowns are good and interceptions are bad, right?

And gaining yards when throwing the ball is better than not gaining yards, right? 

Those elements are really the backbone of the passer rating statistic.  Some don't like the mix.  Perhaps too much weight is given to some aspects and too little to others, but regardless, it's hard to argue that higher is not better and that lower is better when it comes to the rating.  There is at least some evidence that the best individual passing seasons in NFL history have yielded the highest passer ratings (Peyton Manning 2004/121.1, Tom Brady 2007/117.2, etc.).  And it's not merely coincidence that some of the worst quarterbacks in NFL history have very low passer ratings.  So let's take this statistic for what it currently is:  a useful, but flawed representation of how good a QB throws.

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