Defense Since Seattle

[Tony2046]

Joe Flacco is the best QB we've played in the last 5 weeks. This defense has performed well, in that it's done exactly what a capable defense should do to the slate of awful offenses we've played. But there's a reason why we're still in the bottom half of defensive DVOA leaguewide even while being #1 in points against, and it's because this stretch has been defined as much by the terrible offenses and terrible QB's we're playing as by the Pats' actual performance.

Not trying to be a Debbie Downer here, I'm encouraged by how the defense is developing just like everyone else. I feel better about them now than I did 2 months ago, and now that we've basically ended Denver's season I don't really fear any defense we may have to play on the way to another SB run. I think the Pats are likely to outscore anyone left in our way, and the defense obviously has a role in that. But for whatever reason people at every level seem to just ignore strength of schedule when doing comparative analysis. This is one of the more egregious cases of it, right up with people who diminish Brady by pointing out how the Pats 'only' lost 5 wins between 2007 (when we played and beat every AFC playoff team) and 2008 (when we had the easiest schedule in the league).

Good stuff FTW.

But does DVOA account for individual play, personnel changes or other changes throughout the season?

I know they track individual performances but is that incorporated into DVOA?

 

[BradyFTW!]

Good stuff FTW.

But does DVOA account for individual play, personnel changes or other changes throughout the season?

I know they track individual performances but is that incorporated into DVOA?

Individual play: no. DVOA is tracked for individual players, but that's a separate stat that isn't directly related to this one. What I quoted was the team defensive DVOA ranking, so it would not directly account for changes in personnel. It does account for strength of opponent, but not for individual week-to-week lineup changes (so, for example, it does not account for the fact that we played Landry Jones rather than Roethlisberger).

I did quote weighted DVOA, though, and the difference between weighted and unweighted is that weighted DVOA places a greater level of importance on recent performances. I think this roughly approximates the effect that you're describing. FWIW, the Pats are currently 17th in weighted DVOA (.5% better than league average) and 20th in unweighted DVOA (2.9% worse than league average), so we're trending in the right direction. I expect these numbers to move further in a good direction once week 15 is factored in, although that will likely come at the expense of our offensive DVOA taking a hit.

 

[Tony2046]

Individual play: no. DVOA is tracked for individual players, but that's a separate stat that isn't directly related to this one. What I quoted was the team defensive DVOA ranking, so it would not directly account for changes in personnel. It does account for strength of opponent, but not for individual week-to-week lineup changes (so, for example, it does not account for the fact that we played Landry Jones rather than Roethlisberger).

I did quote weighted DVOA, though, and the difference between weighted and unweighted is that weighted DVOA places a greater level of importance on recent performances. I think this roughly approximates the effect that you're describing. FWIW, the Pats are currently 17th in weighted DVOA (.5% better than league average) and 20th in unweighted DVOA (2.9% worse than league average), so we're trending in the right direction. I expect these numbers to move further in a good direction once week 15 is factored in, although that will likely come at the expense of our offensive DVOA taking a hit.

Really good stuff FTW. Thanks

 

[Soul_Survivor88]

DVOA is slanted towards yards, I don't think the defence is something like #20. Think Defensive SRS captures the true ranking of the defence better. In terms of DSRS the team is sixth after yesterday's game (they were eighth or ninth before that). Right now in DSRS the top-ten is:

1) Broncos 6.2
2) Seahawks 5.9
3) Chiefs 4.7
4) Giants 4.5
5) Vikings 4.2
6) Patriots 3.9
7) Ravens 3.5
8) Cowboys 3.3
9) Steelers 3.0
10) Texans 2.0

DVOA through this week won't be available till Wednesday, but I doubt there will be significant change. DVOA top ten through last week is

1) Broncos -17.5
2) Ravens -15.5
3) Cardinals -14.2
4) Giants -13.5
5) Eagles -12.0
6) Seahawks -11.4
7) Vikings -11.0
8) Chargers -5.8
9) Steelers -4.7
10) Buccaneers -4.5

Looking at the respective lists I would personally lean towards DSRS.

In case anybody needs some clarification on these terms

(Defense/Offensive) Simple Rating System vs. Defense-adjusted Value Over Average

Simple Rating System (SRS) via Pro-Football Reference: Uses a team's point differential and strength of schedule to assign a rating to each team, with 0.0 considered average. The difference in two teams' SRS ratings can be considered to be a point spread should they play each other, disregarding home field advantage.

Defense-adjusted Value Over Average (DVOA) via Football Outsiders: A method takes every single play during the NFL season and compares each one to a league-average baseline based on situation. DVOA measures not just yardage, but yardage towards a first down. Performance is also adjusted for the quality of the opponent. DVOA is a percentage, so a team with a DVOA of 10.0% is 10 percent better than the average team, and a quarterback with a DVOA of -20.0% is 20 percent worse than the average quarterback. Because DVOA measures scoring, defenses are better when they are negative.

 

[Tony2046]

In case anybody needs some clarification on these terms

(Defense/Offensive) Simple Rating System vs. Defense-adjusted Value Over Average

Simple Rating System (SRS) via Pro-Football Reference: Uses a team's point differential and strength of schedule to assign a rating to each team, with 0.0 considered average. The difference in two teams' SRS ratings can be considered to be a point spread should they play each other, disregarding home field advantage.

Defense-adjusted Value Over Average (DVOA) via Football Outsiders: A method takes every single play during the NFL season and compares each one to a league-average baseline based on situation. DVOA measures not just yardage, but yardage towards a first down. Performance is also adjusted for the quality of the opponent. DVOA is a percentage, so a team with a DVOA of 10.0% is 10 percent better than the average team, and a quarterback with a DVOA of -20.0% is 20 percent worse than the average quarterback. Because DVOA measures scoring, defenses are better when they are negative.

Thanks