Stats-deluded writer argues "there are no great defenses left in the playoffs" & NE doesn't count

[Ring 6]

I think DVOA is an useful stat. Unlike ESPN's QBR for example it is well thought-out and reasoned. It has its weaknesses though. One is as @convertedpatsfan said, it apparently places too much emphasis on strength of schedule that it appears as if it's almost better playing a good team and losing bad than playing a bad team and winning good.

Another issue is that it's yardage based and hence struggling with bend-but-don't-break defenses. Let's not talk about the Pats, talk about KC's defense. They were 7th in scoring D (and 7th in points per drive). But 24th in yardage. They made up for that disparity by being the best team at taking away the ball. They rank 14th in DVOA.

Or combine both schedule and yardage and talk about San Diego's D. They rank 8th in DVOA. They had Oakland, Atlanta, New Orleans on their schedule. But in raw stats they are 29th in points allowed, 23rd in points per drive. But 13th in yards per drive. Yes, their D was put into bad field position by the offense turning the ball over so often. But a top 10 D?

I think finding a middle ground between SRS (which is points based but also incorporates strength of schedule) and DVOA is a good measure. In terms of defensive SRS the Patriots are #3 after Denver and the Giants and KC 5th. Arizona tied for 16th and San Diego tied for 28th.

Using KC is a great example.
If you allow yards that do not add up to points those yards do not have the same value as yards that do not add up to points.
DVOA is essentially saying, simplistically, who wins the play, and whoever wins the most plays is best. That would seem to be sensible but is not an accurate gauge of who is a better football team.

 

[RobertWeathers]

Not really. Its a statistic calculation that throws a bunch of stuff against a wall. QB rating is heavily flawed, DVOA is just as flawed, if not more.

With DVOA and QB rating, a bunch of raw numbers are crunched and synthesized without accompanying context.

 

[QuantumMechanic]

Another issue is that it's yardage based and hence struggling with bend-but-don't-break defenses. Let's not talk about the Pats, talk about KC's defense. They were 7th in scoring D (and 7th in points per drive). But 24th in yardage. They made up for that disparity by being the best team at taking away the ball. They rank 14th in DVOA.

Yardage-based yes, but situationally yardage-based. They assign "success points" based on down & distance combinations and that's what the stats are created from. And the point values, weightings, etc. are tweaked occasionally via regression runs to increase the correlation between win percentage and DVOA. They absolutely have flaws, but the "it's a piece of garbage they threw against the wall" stuff from butthurt commenters who probably can't take a square root is BS.

Here's their high-level explanation:

Doing a better job of distributing credit for scoring points and winning games is the goal of DVOA, or Defense-adjusted Value Over Average. DVOA breaks down every single play of the NFL season, assigning each play a value based on both total yards and yards towards a first down, based on work done by Pete Palmer, Bob Carroll, and John Thorn in their seminal book, The Hidden Game of Football. On first down, a play is considered a success if it gains 45 percent of needed yards; on second down, a play needs to gain 60 percent of needed yards; on third or fourth down, only gaining a new first down is considered success.

We then expand upon that basic idea with a more complicated system of “success points,” improved over the past few years with a lot of mathematics and a bit of trial and error. A successful play is worth one point; an unsuccessful play, zero points with fractional points in between (e.g., eight yards on third-and-10 is worth 0.54 “success points”). Extra points are awarded for big plays, gradually increasing to three points for 10 yards (assuming those yards result in a first down), four points for 20 yards, and five points for 40 yards or more. Losing three or more yards is -1 point. Interceptions occurring on fourth down during the last two minutes of a game incur no penalty whatsoever, but all others average -6 points, with an adjustment for the length of the pass and the location of the interception (since an interception tipped at the line is more likely to produce a long return than an interception on a 40-yard pass). A fumble is worth anywhere from -1.7 to -4.0 points depending on how often a fumble in that situation is lost to the defense -- no matter who actually recovers the fumble. Red zone plays get a bonus: 20 percent for team offense, five percent for team defense, and 10 percent for individual players. There is a bonus given for a touchdown, which acknowledges that the goal line is significantly more difficult to cross than the previous 99 yards (although this bonus is nowhere near as large as the one used in fantasy football).

(Our system is a bit more complex than the one in Hidden Game thanks to our subsequent research, which added larger penalties for turnovers, the fractional points, and a slightly higher baseline for success on first down. The reason why all fumbles are counted, no matter whether they are recovered by the offense or defense, is explained in FO Basics.)

Every single play run in the NFL gets a “success value” based on this system, and then that number gets compared to the average success values of plays in similar situations for all players, adjusted for a number of variables. These include down and distance, field location, time remaining in game, and the team’s lead or deficit in the game score. Teams are always compared to the overall offensive average, as the team made its own choice whether to pass or rush. When it comes to individual players, however, rushing plays are compared to other rushing plays, passing plays to other passing plays, tight ends to tight ends, wideouts to wideouts, and so on.

 

[libra957]

What we need is a custom schedule, one with the toughest teams.

 

[Soul_Survivor88]

This is really annoying. What will these "analysts" say if we shutdown Big Ben, Bell, and Brown?





I kid you not guys. I really want to advance and have us face the Falcons. Brady vs. Rodgers sounds amazing, but our defense getting the validation it finally deserves would be just as impressive