2011 49ers Season: Statistical Anatomy of a Turnaround

AUTHOR'S NOTE: This post is a more-in-depth version of the infographic David posted earlier today. Several of the themes overlap, so consider what you read here a text-based supplement to the pretty picture created by Beyond the Box Score.

Each Thanksgiving, millions of people travel home to celebrate with their family. It's only fitting then that I cyber-travel from Football Outsiders back to my internet home, Niners Nation, to celebrate the 9-1 San Francisco 49ers with my extended football blogging family. No doubt, there's a lot to celebrate about this team, not the least of which is that, for the first time since the pre-NN days, they're actually a relevant NFL squad in late November.

The question I'm going to try to answer today -- with statistics, of course -- is, "How did they get here?" We know what's changed in terms of what we've seen with our eyes. For instance, this year's team plays much smarter than those of recent vintage: gone are the stupid false starts, delay of game penalties, and blown coverages that made us want to throw a brick through our televisions. Heck, in the space of one lockout-shortened offseason, the 49ers have seemingly gone from the second-dumbest team in the NFL -- the Raiders are always the dumbest, obviously -- to one of the smartest.

Although our eyes are a vital source of football perception, statistics can help to supplement what we see, and provide additional nuance about things to which we may not have paid much attention. In addition to watching (and charting) plenty of game film at Football Outsiders, we evaluate teams using a play-by-play efficiency measure called defense-adjusted value over average -- DVOA for short.

After the jump, an in-depth look at the statistical improvements that have fueled the 49ers turnaround in 2011...

Despite its complicated name, DVOA is a pretty simple statistic that does a very good job of explaining why teams win or lose (See here for a detailed explanation). Essentially, DVOA is just a team's play-by-play success rate, adjusted for opponent and game situation. For instance, the 49ers' current total DVOA of +23.3 percent means that, all else being equal (i.e., average opponents, average game situations), their plays have been 23.3 percent more successful than the average NFL team; good for fourth-best in the league. For your brain's sake, I'm going to focus on DVOA rankings because that's a language everyone can understand no matter his or her mathematical acumen.

So, without further delay, let's dive right into what Football Outsiders' statistics reveal as having fueled San Francisco's massive, warp-speed turnaround in 2011.

IMPROVEMENTS ON OFFENSE

Much has been made about the 49ers' improved running game this season, which I'll get to shortly, but the bigger change on offense has been in the passing game. Last season, with a revolving door of quarterbacks, San Francisco's pass offense finished 24th according to DVOA. This year, it's ranked seventh.

Getting into the weeds a little bit, that improvement has been driven by two things: (1) Alex Smith isn't throwing interceptions as frequently, and (2) the pass offense overall has been much better on third down. In 2010, Smith threw interceptions on 2.9 percent of his dropbacks (i.e., attempts plus sacks), but that's dropped all the way to 1.4 percent so far in 2011. In terms of third-down passing, the 49ers were a below-average team last season, ranking 23rd in DVOA for that situation. This season, they're an above-average unit that ranks 11th.

Turning to the run offense, their overall DVOA ranking is actually worse this season (22nd vs. 17th). However, they're doing three things much better in 2011 than they did in 2010, and those improvements are making them more pleasing to the eyes: (1) running outside better and more often, (2) running better in the open field, and (3) running better on first down.

For anyone who used to read my Niners Nation material back in the day, one of my pet peeves about San Francisco's offense the past several years was its soul-crushing predictability. One way in which this manifested itself was that everyone in the stadium knew that their runs were going up the middle. Indeed, last season, they ran in that direction about 63 percent of the time, and only ran outside the tackles about 15 percent of the time. So far in 2011, they've brought their up-the-middle rate more in line with the league average frequency (49 percent), and have nearly doubled their frequency of outside runs (27 percent).

In addition to running outside more, they've also become increased efficiency by leaps and bounds on such runs, especially those to the outside right. Specifically, after finishing 2010 ranked 27th in this run direction, they're currently the No. 1 unit in the league. It turns out, however, that, as I mentioned earlier, their runs in every other direction have either gotten less efficient or have remained just as efficient as last year. That's beside the point, though. In my mind, the biggest effect of this year's change in direction -- so to speak -- has been to force opposing run defenses to actually play run defense. In other words, the mere fact that they're less predictable this season has opened things up for the rest of the offense.

With respect to open-field running, the scuttlebutt last season -- even before he got injured -- was that Frank Gore had lost a step, with part of the evidence for this being his seeming inability to turn a 5-yard run into a 50-yard run. At Football Outsiders, we have two stats to measure this kind of thing. First, there's second-level yards per carry (2LYPC), which only considers rushing yards gained between 5 and 10 yards past the line of scrimmage. In other words, if Gore has consecutive 8-yard runs, then his 2LYPC is 3.0. Second, there's open-field yards per carry (OFYPC), which only considers rushing yards gained more than 10 yards beyond the line. So, if Gore has consecutive 40-yard runs, then his OFYPC is 30.0.

According to these two stats, intuition was probably right in 2010: The Niners run offense (i.e., Gore and his injury replacements) ranked 26th in 2LYPC and 20th in OFYPC. This year, however, these rankings have been turned on their heads, as essentially the same unit (plus Kendall Hunter) currently ranks 11th in 2LYPC and fifth in OFYPC.

Finally, the 49ers' run offense has become an elite unit on first down (fifth) after ranking near the bottom of the league last season (28th). As was the case with their improvement in outside running, the benefit of increased efficiency via first-down runs is more than just the yardage per se; it also has the happy byproduct of making the offense more flexible in its play-calling. On 2nd-and-long, defenses can anticipate pass with high confidence. On 2nd-and-short or 2nd-and-medium, it's much harder to predict what's coming.

IMPROVEMENTS ON DEFENSE

While many people, including some of my closest friends, were threatening to burn me at the stake for questioning the 49ers defense in recent years, I could never get past the fact that their pass defense got abused against teams that were good enough to exploit it, and that the defense overall seemed to fold just when the team needed them most (See last year's Falcons game). Well, getting much better in both of these areas has contributed greatly to San Francisco's six-win improvement through the first 10 games of 2011.

Last season, the 49ers' pass defense ranked 24th in the league according to DVOA. This season, it's seventh-best. Furthermore, this improvement has been evident on both first and second down, where they've gone from 25th to ninth and 19th to fifth, respectively.

Regarding the defense's overall ability to close out games, their statistical ranking last year in late-and-close game situations (i.e., second half of game with score gap less than 8 either way) conformed nicely with my subjective view: they ranked 21st. This season, they've finished like Singletary wanted them to, but was never able to get them to. Through 10 games, the Niners own the fifth-best defense in the NFL when the game is on the line.

IMPROVEMENTS ON SPECIAL TEAMS

As other pundits have cleverly pointed out, Jim Harbaugh has coached up the 49ers to play Singletary-style football better than Singletary himself ever did: Mistake-free, ball-control offense plus great defense plus great special teams equals wins. As is often the case, the least heralded of the three units so far this season has been the special teams. After finishing 2010 ranked 21st in special teams DVOA, they're currently ranked second, and were ranked first the entire season until Sunday's Keystone Kops routine on field goals.

In large part, the overall improvement in special teams has been due to winning the field-position battle on kickoffs, both in coverage and returns. Last season, their kickoff coverage unit was the third-worst in the NFL; this year it's the eighth-best. Similarly, the kick return unit ranked 22nd in 2010; it's currently fourth in 2011.

IMPROVEMENTS ON HIDDEN THINGS

I'll finish up with a few things that the 49ers have improved at, but have exerted more of a covert influence on the team's turnaround. They're statistics that are not unrelated to performance and wins so much as they're indirectly related.

The one hidden improvement that's probably done more for the psyche of Niners Nation than anything else is that San Francisco is a much (much!) more consistent team in 2011 than they have been in recent memory. In fact, even going back to the Mooch days, I can't remember the last time you knew exactly what you were going to get each week from this team.

At Football Outsiders, we have a statistic called "variance," that tells us how consistent a team's efficiency has been from game to game. Last season, San Francisco was the fourth-least consistent team in the NFL, which shouldn't surprise any of you. This season, however, they're the fifth-most consistent. A big reason for this increase in week-to-week consistency is that they're no longer a horrible road team. Namely, their road offense DVOA ranking has jumped 13 spots, and their road defense DVOA ranking has jumped 12 spots.

The final two hidden improvements have to do with the aspects of the game that have as much to do with luck as anything else, both of which concern the 49ers defense. First, that unit has been one of the healthiest in the league so far, with starters having missed a combined 5 games out of a possible 110: Dashon Goldson's missed two, Donte Whitner's missed one, and Ray McDonald's missed one.

Second, the defense has recovered fumbles at a rate that suggests the footballs are bouncing their way. Specifically, of the 15 times their opponents have fumbled, San Francisco has recovered 10. Fumble recoveries are random events, so the 49ers defense has essentially won a coin flip 17 percent more often than they should have. Obviously the footballs their playing with are not akin to loaded dice, but the fair dice coming up craps a few more times this season might have left them with a worse record. A concrete example of this is Goldson's sideline-defying fumble recovery that sealed the Niners' win over the Eagles. One could reasonably argue that that win -- ultimately the result of a fortuitous bounce -- signaled their arrival to playoff contention, cemented the players' faith in Harbaugh, and propelled them to six more wins in a row (so far).

BOTTOM LINE

It doesn't take statistics to realize that the 49ers are a much better team this year than last. However, statistics can help to shed light on some of the specific manifestations and mechanisms behind their improvement. To wit, the main stat-based differences between 2010 and 2011 are as follows:

1. The pass offense is more efficient overall, mostly because Smith is throwing fewer interceptions and that they're much better on third down.
2. The run offense has gotten better at utilizing carries to the outside, gaining extra yards downfield, and efficiency on first down. Each of these has helped make the offense less predictable overall, which has had residual effects on the passing game.
3. The pass defense is much more efficient.
4. The defense as a whole doesn't fold anymore when the game is on the line.
5. The special teams has contributed more towards winning the all-important field position battle, especially on kickoffs.
6. The team's week-to-week performance is more consistent, largely because they actually show up to road games now.
7. They've been very lucky on defense in terms of health and fumble recoveries.