Playing at your best
By Stephen J. Dubner
As we head into the first weekend of the NFL playoffs, the conversation shifts. No longer are we talking about the long arc of the season -- about working out the kinks, getting schemes in place, or jockeying for position. Now, with every game do-or-die, we're talking about teams peaking at the right time. No matter how good or bad a team's record may be, the final summit is in sight; it's time to turn on the juice.
In the latest installment of "Football Freakonomics," we look at the art and science of peaking. What's the best way to assess a team's peak position?
Well, there are a million variables -- things that are being argued over at this very moment across the nation on sports talk radio -- like momentum, injuries, matchups, weather, and so on. A lot of those are relevant.
But there is one metric that seems to be a good indicator of who's peaking and who's not, as identified by Kerry Byrne of ColdHardFootballFacts.com: the passer rating differential (PRD). It's nothing more than a team's offensive passer rating minus its defensive passer rating, but it seems to accurately capture a team's overall play and momentum. In the accompanying graphic, you can see how each team's PRD has changed over the course of the season, and where they're positioned now.
Here, ranked in order of their season-ending PRDs, are the 12 teams still in contention:
1. Green Bay (42.01)
2. New Orleans (24.06)
3. Houston (23.68)
4. New England (19.58)
5. Pittsburgh (17.95)
6. San Francisco (17.89)
7. Detroit (15.13)
8. Baltimore (12.83)
9. Atlanta (7.75)
10. New York Giants (6.76)
11. Cincinnati (-5.42)
12. Denver (-19.67)
Houston's PRD is the biggest surprise, though the stat doesn't account for playoff experience, of which the Texans have zero. The most remarkable number, of course, is Denver's negative PRD.
As a Steelers fan, I am hardly comforted by Pittsburgh's relatively robust PRD of 17.95. Even though the Steelers' defense has been extraordinary, Rashard Mendenhall's season-ending knee injury leaves the rushing duties to be covered by undrafted free agents Isaac Redman, John Clay and the newly signed Chad Spann. On the other hand, James Harrison was undrafted too, and that's worked out pretty well.
If nothing else, this turn of fate suggests an avenue for future research: evaluating overall team success with respect to roster-wide draft positions. Just for kicks, here's a look at one writer's list of the top 25 undrafted players in NFL history.