August 16, 2009

Measuring Effectiveness of An NFL play

Filed under: Uncategorized — wwinston @ 8:29 pm

In spring a young man’s fancy turns to love, but in the fall it turns to NFL football!  How should we evaluate a running back or QB? Most running backs are judged on yards per carry. QB’s are juded on a ridicuously complex absurd system.  

   Really the value of say a 3 yard gain depends on the situation.A 3 yard gain on 3rd and 3 at midfield is much better than a 3 yard gain on 3rd and 10 at midfield. My colleague Jeff Sagarin and I have solved this problem by determing a point value for any possible play. See my new book Mathletics  for details of how point values are determined.

For example , a 3 yard gain with 3rd and 3 at midfield is worth around 1.2 points while a 3 yard gain with 3rd and 10 at midfield is worth around -0.40 points.

Using every play for the 2008 NFL season we found that a passing play on  average generated 0.19 points of value while a running play on average generated only 0.08 points of value. Teams pass around 55% of the time, so they seem to realize that the pass is on average a better call.

     The pass, however, is riskier than the run. The standard deviation of points gained per passing play is 1.56 points the standard deviation of points gained per run is only 1 point.

  So here we have an “asset allocation” problem reminiscent of portfolio optimization in finance. Stocks are on average a better investment than bonds but bonds are less risky so people usually hold both investments in their porffolio.

Tune in later this week for a listing of last season’s best passing and running offenses and defenses and a list of the NFL’s best QB’s and running backs by this new measure of effectivness.

No Comments »

No comments yet.

RSS feed for comments on this post. TrackBack URL

Leave a comment

Powered by WordPress