Offhand, do you have any idea what the equation below represents? (And no coaching from the math majors in the group.)
Me neither. Or at least I didn’t have until I tried to make sense of this article, which attempts to quantify in numeric terms what common sense should already tell you — that the team that turns the ball over the fewest number of times in the course of a game or season tends to win more often than its more generous opponent.
According to the authors of this cheery little tome, “the correlation between winning percentage and turnover differential is equal to 0.646 (3SF). This suggests a strong positive correlation between turnover differential and win percentage.”
Having it expressed in such a manner may be only slightly less odious than having John Madden bellow it at the top of his lungs, complete with grunting noises and wild arm waving. Still, you get the point — that Redskin defensive coordinator Jim Haslett was definitely onto something when he put turnovers at the top of his priority list when he took the job and again this spring when the team drafted a trio of defensive backs whose distinguishing characteristic is their ability to produce interceptions.
Altogether, the Redskins intercepted 21 passes in 2012 while having only eight of their own picked off. Likewise, Haslett’s forces recovered 10 fumbles while the offense was losing only six. The result was a turnover differential of +17 for the season, which ranked third in the NFL after New England (+25) and Chicago (+20).
Not surprisingly, that translated to success on the field for all three teams. The Patriots went 12-4 and won their division, while the Bears missed the playoffs but still turned in a 10-6 record — identical to the Redskins’ mark. In all, five of the NFC’s top seven teams in turnover differential made the playoffs, while in the AFC, it was six of seven.
Going back to the article referenced above, the authors make it clear they are only measuring statistical probability, not causality. In other words, it isn’t clear from the numbers whether teams win because they generate turnovers or because the excellent players who happen to populate good teams just happen to be more likely to produce interceptions and fumbles than the less-talented players on losing teams.
In the case of the Redskins, I’ll go out on a limb here and suggest it’s more likely to be the latter — and specifically the almost unprecedented ability of RGIII to avoid throwing picks — that ranks them among the elite in terms of differential. Indeed, while the Redskins’ total of 21 interceptions was tied for the second-most in the NFL in that category (the Bears led the league with 24 and the Giants also picked off 21), they only managed to recover 10 fumbles — putting them 10th in the NFC.
Statistically speaking, while the Redskin defense was pretty solid in terms of taking the ball away from its opponents, the key to the team’s +17 turnover differential was RGIII only throwing five interceptions all season long in 393 attempts, which translates to one interception every 78.6 attempts.
To put that in perspective, only Tom Brady was better, throwing eight interceptions in 637 attempts, for a rate of 1 to 79.6. Among other notable quarterbacks:
• Aaron Rodgers — eight interceptions in 552 attempts, or 1 to 69;
• Colin Kaepernick — three INT in 218 attempts, or 1 to 72;
• Peyton Manning — 11 INT in 400 attempts, or 1 to 53;
• Ben Roethlisberger — eight INT in 449 attempts, or 1 to 56.1; and,
• Russell Wilson — 10 INT in 393 attempts (exactly the same number as RGIII, coincidentally), or 1 to 39.3.
So what have we learned, class? First, we’ve learned that reading scholarly articles can leave you with a throbbing headache. But beyond that, we’ve learned that the numbers reinforce what our eyes saw. RGIII, by any measure, had a phenomenal season and the key to repeating that success is to keep him out of the fracture ward. And assuming he either can’t stay entirely healthy or regresses to something approaching the statistical mean in his sophomore season, the Redskins had better hope all the ball-hawking secondary members they recruited in the off-season are as good as advertised.