Packing the Stats: Rushing to Conclusions
After Sunday afternoon’s 30-20 victory by the Green Bay Packers over the St. Louis Rams, I listened to Jason Wilde’s weekly appearance on ESPN Wisconsin’s radio show “Pack Attack.” The conversation immediately dove into a debate between Wilde, Bill Johnson, and Homer about the effectiveness of Alex Green’s rushing attempts. While he made 20 rushing attempts the entire game, Green only netted 35 yards for a 1.8 yards per carry average. His longest run was for 15 yards.
On one side of the debate was Jason Wilde, who maintained that making the attempts to run the ball was more important than their overall yards per carry. He posited that the defense’s linemen would have to account for a run, even if it wasn’t for significant yardage. That means they couldn’t just “pin their ears back” and go after the quarterback each down.
Opposing this idea was Bill and Homer, who both insisted that Green’s yards per carry was unacceptable and would need to get better in the future to ensure offensive success. They claimed that if the running game isn’t making traction, then the defense doesn’t really have to worry about it, period. (Jason Wilde eventually called them “stubborn” in their opinions.)
So which matters more – yards per carry or total rushing attempts? This really piqued my interest from a statistical standpoint, and I decided to head over to Pro-Football-Reference.com to being my research. My sample data was all games (regular season and postseason) within the past ten years (2002-2011) that matched the rushing criteria below.
(You can download the complete Excel file here: rushing_stats.xlsx)
|TOTAL RUSHING YARDS PER GAME (2002-2011)|
|TOTAL YARDS||W||L||T||W-L%||COUNT||GBP W-L%||GBP COUNT|
|AVERAGE YARDS PER ATTEMPT (2002-2011)|
|YDS/ATT||W||L||T||W-L%||COUNT||GBP W-L%||GBP COUNT|
|TOTAL ATTEMPTS PER GAME (2002-2011)|
|ATTEMPTS||W||L||T||W-L%||COUNT||GBP W-L%||GBP COUNT|
These results, I think, are extremely interesting, and they help support the case made by Jason Wilde. One of the most surprising things is how little of a correlation there is between yards per attempt and winning games. The data suggests that anything after 2.0 YPC is not much different than flipping a coin to see who wins. While correlation does not equal causation, the correlation is pretty low, so having a big YPC average doesn’t automatically mean a better chance of winning.
Now, contrast that with total attempts per game, and the difference is quite striking. The chance of winning a game increases significantly with every additional 5 attempts made per game. Even in total rushing yardage, the success rate goes up as the yardage goes up.
If we look at this with some hypothetical numbers, things become a little more obvious. Let’s say Team A runs for 100 yards in a game on 25 carries. The average yards per attempt would then be 4.0. Good production all around, I would say. (While each statistic individually gives about a 50% chance of winning per the charts, please note that we haven’t looked at the success rate given statistical combinations or cross-references.)
Now, let’s say Team B also runs for 100 yards in a game, but they only do it on 10 carries. That’s 10.0 YPA, but can an offensive be sustained for an entire game off of 10 carries? Also, the numbers could suggest more of a boom-and-bust running performance. Big plays are good, but if they can’t be sustained with longer drives, it gives the other team more time to score.
Similarly, if Team C matches the YPA of Team A with 4.0, but they only do it on 15 carries, that’s just 60 yards for the entire game. If you don’t have a big passing attack to balance out the offense, it could make it harder to win.
Which brings me to my next point. You’ll notice that the Green Bay Packers’ winning percentages are almost all higher than the league totals. This can be attributed to the fact that, in the past ten years, the Packers have had some of the best passing offenses in the league with Brett Favre and Aaron Rodgers. They don’t need as strong of a running game when they can make things happen through the air.
For example, in the 80-99 total yards category, the Packers (68.60%) are well above the league winning percentage (39.36%). Other teams in the past ten years to be significantly higher in this category are the New England Patriots (75.80%) and Indianapolis Colts (57.60%).
If we look at the attempts per game in the 20-24 range, the Packers (42.50%) are almost double the average (24.00%). Again, other teams significantly higher in this category are the Indianapolis Colts (58.10%), New England Patriots (57.10%), Philadelphia Eagles (39.00%), and New Orleans Saints (37.00%).
Notice anything yet? All of those other teams have boasted some pretty significant passing attacks.
Finally, we do have one more things to take into account. Football Outsiders devoted themselves to debunking the myth that a team has to “establish the run.” In their 2012 Almanac, they write:
. . . There is no correlation whatsoever between giving your running backs a lot of carries early in the game and winning the game. Just running the ball is not going to help a team score; it has to run successfully.
There are two reasons why nearly every beat writer and television analyst still repeats the tired old school mantra that “establishing the run” is the secret to winning football games. The first problems is confusing cause and effect. There are exceptions, but for the most part, winning teams have a lot of carries because their running backs are running out the clock at the end of wins, not because they are running wild early in games.
The second problem is history. . . Optimal strategies from 1974 are not optimal strategies for 2012.
Their conclusions are drawn in a 2003 article (their first ever) that looks at first quarter running production vs. fourth quarter running production, then comparing that to success during the season. My only concern with this approach is that it’s a little short-sighted and doesn’t have a big sample size. Is the sample size significant enough? Sure, but we could be looking at a bigger picture. Plus, they’re only looking at two quarters of a game, which doesn’t really speak to an overall running performance.
Obviously, there is more to winning a football game than just running the ball. Offenses have to have some semblance of balance in order to be effective. As Football Outsiders notes, simply giving carries to the running back is not a solution. Still, if you consider the effect it has on a pass rush against an elite quarterback like Aaron Rodgers, there is some substance to the strategical advantages.
And as I mentioned before, correlation does not equal causation. There are so many aspects to the football game – e.g., defense – that can make a much bigger difference in regard to the outcome. Yes, being able to run more yardage on more attempts correlates to a higher rate of success, but in order to get those attempts, you have to perform well in other areas.
Finally, the point from Football Outsiders about being able to run the clock out on those extra attempts to seal a game is about as important as the rest of it. Teams that can add those extra carries and still be productive to maintain a lead will generally be picking up more wins.
All that said . . . who do you think wins this debate? Jason Wilde or Bill and Homer?——————Follow @ChadToporski