Re-Evaluating Running Back Metrics
by Bill Barnwell
In the past, Football Outsiders has come under criticism from fans who think our core metrics -- DVOA and DYAR -- don't take into account the explosive nature of players whose astounding athleticism and ability to make defenders miss goes beyond the scope of statistics. While we haven't discounted the impact that those sort of players can have on an isolated play in a game, it's been difficult for both writers and readers both to reconcile themselves with the idea that players considered stars by the media and valuable assets by their teams are drastically overrated because of their "boom or bust" style.
When Mike Tanier and I were discussing the likelihood of Reggie Bush accruing 45 rushing DYAR in the 2008 season, I knew it was an easy bet. I like to argue with Mike about something every August just to stretch my debating muscles before the season. It's an important part of FO training camp, right up there with getting the new Week In Quotes guy to jump on a table and recite famous Herm lines.
I was debating what to set the bar for Bush's rushing DYAR and counting my chickens when it hit me. I thought to myself, "The only way Bush even hits positive DYAR is if we start including..."
That was August 2008; seven months have passed, and with them, I've been hard at work putting together our revolutionary new statistic:
There have been plenty of long nights watching game tape, trying to figure out exactly what the baselines should be for things like stutter-steps above replacement. I've sent hundreds of e-mails to groundskeepers around this great nation trying to convince them that they need to draw horizontal yard-lines across the field without a single reply. I've spoken with several upstart football leagues and tried to convince them that they should consider the 6.124 yards between hashmarks the "Indie First Down" and allow teams a chance to at least replay the down if they can maneuver the ball from one hash to the other. I faxed each team a warning to prepare their scoreboards, adding space for Horizontal Yards and cautioning them to change their "yards" indicators to "Vertical Yards." Strangely, this resulted in the Raiders making me a job offer. I've even pitched Aaron on going back to a version of our old slogan: "Football To And Around The Hashmarks" is catchy, but I guess it doesn't fit well on a cafepress.com t-shirt.
More importantly, though, I've gone through every NFL game from the 2008 season, watching brilliant backs like Bush make initial tacklers miss before being brought down by the second wave of tacklers that caught up to him while he was making the initial tackler miss. I've seen Tim Hightower bounce a play designed to be off-tackle out to the industrial fans and Gatorade table. I've gazed in admiration as Dominic Rhodes ran the sweep like he was under the aegis of a Nintendo controller, operating on two axes. Finally, I thought to myself night after night, I understand how Adrian Peterson tap-dancing in the backfield like he was waiting for a storm to pass begat a successful NFL rusher. I scoffed at the failures of the Large Hadron Collider; by the time they'd found Higgs Boson, I'd know how many horizontal yards Mark Higgs and Cap Boso had accumulated.
As I finally compiled the final totals and began the calculations for horizontal yards last week, I began to shudder with the thought of what might be on the other side. Would I blow the lid off conventional wisdom, proving that DVOA and DYAR were right about boom-or-bust runners? Would horizontal yards prove to be an excellent indicator of performance that Football Outsiders had failed to incorporate into its projections and metrics?
The answer is yes.
|Rank||Team||Horizontal Yards||Rank||Team||Horizontal Yards|
As you can see, horizontal yards bears a significant relationship to success by virtue of the fact that its top two teams -- Tennessee and Minnesota -- both made the playoffs. Included in the top ten are playoff teams like Indianapolis, the New York Giants, Atlanta, and the Super Bowl Champion Pittsburgh Steelers, who would have ranked even higher had Willie Parker been healthy for the entire season.
Of course, I know Willie Parker and horizontal yards seem like a match made in statistically significant heaven, so let's introduce you to the individual stats. For all rushing plays and completed passes, I've calculated both POV (percent over adjusted vertical yards), which is my percentage-based horizontal stat, and POS (parallel yards above adjusted standard), which is my cumulative stat.
We'll start with the backs. Here are the top 15 backs in the league with 30 carries or more by POV:
I'm very excited that Ahmad Bradshaw of my very own New York Giants was the leader in POV for the 2008 season. Because of his speed and sideline-to-sideline ability, the cumulative effect of chasing Bradshaw around the backfield tires out defenses and creates opportunities for Brandon Jacobs.
Although Adrian Peterson had 838 horizontal yards on the season, he only registered a POV of 6.3% because he actually ran for about 890 adjusted vertical yards on the year. We'll have to see if Peterson can turn more of those vertical yards into horizontal ones next year.
One sleeper for 2009: 49ers tight end Delanie Walker. He only had two carries on the year, and they combined for -13 vertical yards, but Walker had an astounding 24 horizontal yards on the two plays, producing a ratio far above anyone else in the league. HAROLD, our horizontal fantasy football projection system (named after former Bengals back Harold Green), is seeing big things for him in the San Francisco offense come 2009.
The top 15 in POV on receiving plays (minimum: 50 targets) reveals the fruits of having a veteran presence on your roster:
Ike Hilliard's ability to stretch the field horizontally makes him an incredibly valuable player, even as he ages; that's something astute fans of the game already know from his accomplished past, though. Upon Hilliard's arrival in New York out of Florida in 1996, the Giants immediately went from 6-10 to 10-5-1 and into the ascendancy in the NFC East. After making it to the Super Bowl in 2000, the Giants began to phase Hilliard out as a starter in 2001, resulting in a 7-9 record; the year after, they returned him to the starting lineup and went 10-6, a clear sign of his importance to the team.
After the Giants went 6-10 in 2004, they magnanimously let Hilliard go to Tampa Bay; the Buccaneers went from 5-11 without Hilliard to 11-5 with him. The year after, Tampa Bay took him out of the starting lineup and immediately went 4-12. Duh. Hilliard became a starter again in 2007, and the result was a 9-7 season and an NFC South crown. Ike Hilliard, my friends, is a winner, and horizontal yards proves it.
Of course, the only way we might ever get to know the true value of every player -- his real worth to his team, the absolute quantifiable measure of his performance and skills -- is if we could somehow combine vertical yards and horizontal yards to create...
I've got some work to do.