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03 Aug 2011

Formation Analysis: Number of RBs Part I

by Danny Tuccitto

With the 2011 season fast approaching, let's finish up our game charting reviews of 2010 with a look at tendencies and performance based on the number of running backs in the formation. Today's focus is on offense; we'll get to defense in Part II.

Overall, 47.2 percent of runs were out of formations with one running back, continuing an upward trend since our game charting project began (45.8 percent in 2009, 43.7 percent in 2008, and 44.0 percent in 2007). Interestingly enough, the trend seems to be being driven by one team, the Colts. After pushing the 90-percent boundary in 2007 and 2008, an even-more-outlying 94.4 percent of Indianapolis' runs over the past two seasons came out of a one-back set. To put that in perspective, the second-most-frequent one-back run offense since 2009 is New England at 76.8 percent.

Seven of the 12 offenses with an above-average run DVOA in one-back sets made the playoffs, which is about double what you'd expect from random chance. Of the five that didn't make the playoffs, the Bucs and Giants both won 10 games. This isn't just a one-year fluke either: Each of the past four seasons, playoff teams have been a minimum of 7.1 DVOA percentage points better than nonplayoff teams on runs from a one-back formation.

That stat probably doesn't bring much solace to Texans fans, who felt the pain of yet another non-playoff season despite having the pleasure of watching the NFL's best running offense from a one-back set in 2010. Since we began charting, only three teams have averaged over six yards per carry on runs from this formation: the 2008 Giants, the 2009 Titans, and the 2010 Texans. Last season, Houston also became the second team since 2007 to have a one-back run DVOA above 35.0 percent, again joining those 2008 Giants.

One last thing worth mentioning is that, given the top three overall run offenses in 2010 were also the best at running from a one-back set, the dissimilar tendencies for Houston, New England, and Philadelphia suggest that there's more than one path to an efficient running game. The Texans were in the bottom quartile of the league in one-back running frequency, the Patriots had the highest one-back frequency among non-Indiana teams, and the Eagles were basically fifty-fifty; but all three excelled in the running game thanks to a proficiency in one-back sets.

In the table, frequency stats represent the percentage of a team's total running back carries that came with various numbers of backs in the formation. For convenience, I’ve ranked teams’ formation-specific run DVOAs, and sorted the table from highest to lowest run DVOA in a one-back set:


OFF DVOA 1 RB Rk DVOA 2+ RB Rk 1 RB Freq. 2+ RB Freq.
HOU 39.1% 1 13.7% 1 35% 65%
NE 30.8% 2 12.0% 2 79% 21%
PHI 24.0% 3 -7.3% 17 54% 46%
KC 21.9% 4 -9.3% 23 51% 49%
TB 12.5% 5 -21.5% 28 37% 63%
NO 8.3% 6 -10.7% 24 39% 61%
MIN 8.2% 7 -8.1% 20 59% 41%
BAL 7.8% 8 -3.2% 11 35% 65%
JAC 5.7% 9 9.4% 4 25% 75%
NYG 5.5% 10 8.2% 5 39% 61%
IND 5.1% 11 -57.7% 32 95% 5%
NYJ 0.6% 12 9.7% 3 39% 61%
SF -2.3% 13 -4.5% 14 43% 57%
ATL -3.2% 14 -8.6% 21 37% 63%
OAK -3.6% 15 4.6% 6 34% 66%
CIN -3.9% 16 -17.5% 27 54% 46%
OFF DVOA1 RB Rk DVOA 2+ RB Rk 1 RB Freq. 2+ RB Freq.
ARI -4.8% 17 -11.2% 26 50% 50%
WAS -6.1% 18 -7.7% 18 48% 52%
TEN -6.1% 19 -4.2% 12 50% 50%
DAL -6.1% 20 -4.2% 13 28% 72%
DET -6.5% 21 -36.4% 31 74% 26%
BUF -7.9% 22 -7.9% 19 51% 49%
MIA -10.7% 23 0.2% 9 22% 78%
GB -10.8% 24 -5.5% 16 32% 68%
PIT -12.1% 25 -1.8% 10 60% 40%
STL -13.6% 26 -22.9% 29 57% 43%
CHI -15.3% 27 -4.9% 15 55% 45%
DEN -18.1% 28 -32.1% 30 65% 35%
SD -19.0% 29 2.9% 8 36% 64%
SEA -19.5% 30 -11.0% 25 58% 42%
CLE -21.7% 31 4.5% 7 37% 63%
CAR -25.3% 32 -9.2% 22 35% 65%
NFL AVG -1.5% -- -7.6% -- 47% 53%

Posted by: Danny Tuccitto on 03 Aug 2011

30 comments, Last at 17 Aug 2011, 5:19pm by Kent

Comments

1
by jklps :: Wed, 08/03/2011 - 1:32pm

Interesting that the Texans were #1 with 2bs with Leach leaving for Baltimore.

2
by Anonymous1 (not verified) :: Wed, 08/03/2011 - 1:37pm

"Seven of the 12 offenses with an above-average run DVOA in one-back sets made the playoffs, which is about double what you'd expect from random chance."

Only 12 out of 32 were above average?

4
by zlionsfan :: Wed, 08/03/2011 - 1:46pm

That's right: remember that the net DVOA of all running plays is not 0. (Only 14 teams had a positive rushing DVOA this season; 23 teams had a positive passing DVOA.)

3
by zlionsfan :: Wed, 08/03/2011 - 1:39pm

While the temptation exists to say "Detroit and Indianapolis get it, but New Orleans and Tampa Bay do not," I think we'd need to see more data before we could reach that conclusion, specifically passing DVOA with 1 RB and 2+ RB, along with frequency of plays from those two groupings, both for pass plays and overall.

If the Bucs and Saints throw well out of two-back sets, then there's an excuse to run somewhat more often than the stats would recommend - you don't want to hold up a giant sign that says "ONE BACK MEANS WE'RE PASSING". On the other hand, if the difference in efficiency is significant, is there really value in repeatedly running plays that you can't execute well just to keep the defense from keying on the plays you do run well?

7
by trill :: Wed, 08/03/2011 - 2:25pm

I agree that passing DVOA out of these sets impacts how we should view teams' choice of 1 vs 2RB. It'd also be nice to see the situational percentages, or maybe eliminate GL carries from the equation. In order to compare apples-to-apples we need a little more context; I don't think 1RB is a very popular or effective choice in GL situations.

1RB is a very different animal than 2RB in how the defense is forced to respond, whether you've got 2TE, an H-back, or 3+WR. With four immediate vertical threats, 1RB essentially prevents the defense from putting 8 in the box.

16
by Aaron Brooks' Good Twin (not verified) :: Thu, 08/04/2011 - 10:07am

Does this system count an H-back lined up off the tackle but also off the line as a 2RB or a 1RB?

17
by Aaron Brooks' Good Twin (not verified) :: Thu, 08/04/2011 - 10:08am

Also, if a team executed a lead QB draw, where the RB dives and acts as a fullback for the rushing QB, is that considered a 1RB rush or a 2RB rush? Are all of Tebows plays counted as 2RB, because he's basically a fullback who throws?

22
by trill :: Thu, 08/04/2011 - 2:03pm

Danny said only RB carries were counted, so any QB draw/dive/scrambles are out.

21
by trill :: Thu, 08/04/2011 - 2:02pm

Good question. Probably varies depending on who charted the game. But I bet they're charting personnel (so a FB is the second RB no matter where he lines up) rather than alignment.

24
by Aaron Brooks' Good Twin (not verified) :: Thu, 08/04/2011 - 6:43pm

Does BJ Raji chart as a FB on goal line plays, or as a DT?

26
by psuasskicker :: Thu, 08/04/2011 - 9:04pm

Guys are charted based on the position in which they line up, regardless of their "natural" position. i.e. When Todd Heap lines up in the Ravens backfield, he's charted as a back, not a TE.

8
by BucNasty :: Wed, 08/03/2011 - 2:32pm

Between the relatively low frequency and the very high per play rating, I think a big reason Tampa Bay scored so highly was from success running the draw on third-and-long. They ran a trap-draw to Cadillac Williams probably once a game after Blount took over as a starter and it seemed like it converted every single time.

5
by Theo :: Wed, 08/03/2011 - 1:48pm

If I counted correctly, 11 teams are worse at running what they run most from.
The NFL for example says they are better at running form the 1-back formation, but they run it less than 2+back formation.
I counted 18 teams that are right, 11 that are wrong and 3 teams run something even.
Am I reading it correctly that these teams are not running into their strength?

9
by trill :: Wed, 08/03/2011 - 3:31pm

I don't think this data tells us all that. It says more about a team's personnel and scheme than anything else. Adding a second RB can protect the ball-carrier from big hits; the FB can be used to cut off backside pursuit, or act as a decoy/dive option. The Packers used their fullbacks last year to allow for more sustained double-team blocks on defensive linemen, rather than having guys get off combo blocks to handle LB's. Traditional angle-blocking teams are gonna use a fullback a lot more, even if they incorporate zone blocking plays. In contrast a team like IND runs nothing but inside/outside zone; while you can run these plays with a lead blocker it's usually more advantageous to use 11 or 12 personnel to take another defender out of the box.

The increase in efficiency with 1RB might be accounted for with something like this: 1st&10 with 21 personnel, run for 2yds (negative DVOA). 2nd&8 with 11 personnel, run for 7yds (positive DVOA). If the defense responds to 11 personnel the way they "should" (obviously contingent upon ability of the specific QB/RB), it really opens up the run game.

11
by Theo :: Wed, 08/03/2011 - 4:09pm

Ok agreed, some teams like the Colts are a perfect fit, because their 11 and 12 personnels are practically the same, they can shift clarke out and their 12 is an 11.
But from what I read is that you twist a negative DVOA on a play into a good thing cause when the defense thinks pass after that, you open up the run game with your 11 personnel.

I find it a good one, but a doubtful one to make it work consistently.

13
by Danny Tuccitto :: Wed, 08/03/2011 - 4:51pm

In prepping for the formation pieces, I've been looking at these relationships between frequency and DVOA out of the same curiosity you're illustrating. Haven't included them in the write-up because I don't want to make any ill-conceived grand conclusions or get into the weeds too much. If it helps your discussion at all, though, 2+RB run DVOA in 2010 was highly related to 2+RB frequency, but 1RB run DVOA was not related at all to 1RB frequency. For the WR formations in 2010, there were no DVOA/freq relationships except for 0-1WR. Of course, keep in mind that the WR formation pieces reported total offense DVOA, not just run DVOA like this one does. Oh, and also, from what I can tell, the pattern of these DVOA/frequency relationships seems to change considerably ever year. Hope this helps.

If you want my two cents, my hunch is that a lot of the "missing" covariation between DVOA and frequency is caught up in the strategies and tactics of the game, which are things that we can't measure without knowing what's going on in the coaches' heads pre-snap.

For instance, HOU being so much better in 1RB despite being a pro-set O w/ a lead-blocking FB (and also having a dangerous pass O) probably has something to do with the fact that defenses know HOU has a pass tendency out of a 1RB set, so they put in nickel or dime personnel. Kubiak, knowing that the opposing D knows their tendency, goes against tendency and runs out of the 1RB set for a big gain. It's like 3rd-level poker thinking, which we can't measure obviously.

18
by Aaron Brooks' Good Twin (not verified) :: Thu, 08/04/2011 - 10:12am

It's not like 2RB was killing Houston. They were the best in the league at 2RB as well. So even when teams knew they were rushing, they ran well.

This might just be me, but it seems like the teams that do poorly in 2RB are also known for having lines that are terrible in power running, and vice-versa. Lions, Eagles, etc, are all bad 2RB teams known for an inability to pick up 3rd-1. The Jets, etc., are good at it, and known as power teams. Which is correlation and which is causation, I'm not sure.

23
by tuluse :: Thu, 08/04/2011 - 4:13pm

The Bears line is awful and they were significantly better from 2 back sets.

6
by chemical burn :: Wed, 08/03/2011 - 2:21pm

How much is Philly's DVOA by Vick taking off and running from 1 back sets? I imagine he was more likely to scramble from that formation and his DVOA would account for the difference between their 1 back and 2+ numbers...

Also, Philly's 2back set number are undoubtedly brought down by the "give eldra buckley the ball six times to run out the clock" strategy that they employed in at least a few blowouts...

12
by Danny Tuccitto :: Wed, 08/03/2011 - 4:29pm

These stats only include RB carries, and don't include any kind of Wildcat-style plays. So, to answer your question, Vick's not factoring into PHI's 1RB Run DVOA at all.

14
by chemical burn :: Wed, 08/03/2011 - 4:53pm

Hm. Interesting. Of course, as has been pointedly out repeatedly, Vick always factors into the running game, technically, just because of the threat he poses to linebackers and safeties on every single play. Still, interesting to see the isolated numbers for RB carries...

19
by Aaron Brooks' Good Twin (not verified) :: Thu, 08/04/2011 - 10:18am

Vick ran for 676 yards on 100 rushes in 12 games. Don't you think excluding his runs might tweak Philly's running DVOA a little? Or Atlanta's historical numbers?

Doesn't that also greatly skew teams like GB, who had QBs finish second in rushing yardage?

20
by chemical burn :: Thu, 08/04/2011 - 12:40pm

Of course it does. But this article is SPECIFICALLY trying to weed out instances of QB's scrambling and tell us exclusively about running back production from certain formations. There's arguably value in that...

10
by Joseph :: Wed, 08/03/2011 - 3:41pm

For teams like the Saints & Pats who had multiple "starting" RB's last year, it might be interesting to separate different backs out. For the Saints at least, it would be interesting to separate out Ivory vs. Bush vs. Julius Jones vs. Pierre Thomas et al. I'm sure that individual DVOA in the Almanac would give us some ideas, but it might be interesting for certain teams. [For Houston, OTOH, it just means that Foster was excellent last year no matter what the situation.]

15
by The Ninjalectual :: Wed, 08/03/2011 - 9:53pm

Just don’t tell this to the Super Bowl Champion Green Bay Packers, who ranked 24th in single back rush offense, and who ran with two or more running backs nearly 70% of the time!

Warren Peace

25
by nuclearbdgr :: Thu, 08/04/2011 - 7:31pm

It would be interesting to see the Packers success rate out of the 'inverted wishbone' 3-back set they ran (and how well they passed out of too).

27
by Bucs Fan (not verified) :: Fri, 08/05/2011 - 2:30pm

I think the most interesting fact (but I am biased) is the Bucs splits.

They have, based on usage rates, the strangest splits in their 1RB/2RB stats. They have the highest ranking discrepancy (#5 in 1RB, #28 in 2RB, for a 23 spot drop). This isn't as extreme percentage-wise as Indy's (-52.6%), simply because Indy is so terrible with 2RB.

*However*, note that TB used 2+RB 63% of the time! Indy, knew their weakness, using 2+RB only 5% of the time. So, looking at the listings, TB was tied for 9th in how often they used 2+RB, while Indy was, by far, dead last. TB was 28th most effective, Indy was the least most effective.

One team avoided their weakness. One team played into their weakness.

30
by Kent (not verified) :: Wed, 08/17/2011 - 5:19pm

It could also mean that becasue the Bucs did not run all that often from the 1 back set teams were expecting pass and ended up getting burned by the run, similar to what someone else mentioned with regards to the Texasn and their much smaller quantity of runs from a 1 back set despite their tremendous efficiency.

It could very well be that if the Bucs began to run the ball 75% of the time from their one back set that their efficiency would drop, and unless they passes more from a two back set their two back efficiency could stay around a similar level. (Of course Ceterus Parabis applies, which is a horrible assumption really)

28
by MaineMan (not verified) :: Sat, 08/06/2011 - 7:24am

I might be interesting to compare these numbers to teams' play-action effectiveness.

29
by Kent (not verified) :: Wed, 08/17/2011 - 5:16pm

Can we do something like this for running with one or two TE's in the game. A lot of teams like to use their TE's as extra blockers in the running game in the 1 back sets, and it might also have a correlation to how well a team passes out of the 1 or 2 TE set.

I.E if you see a team that runs the ball well out of the 2 TE set with 1 back, they may also be quite good at passing from that set as the defense has to have in the back of their mind their ability to run the ball. Playaction probaby also has an impact here.