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For more from Chase and Jason, check out their work at Football Perspective and The Big Lead.

Another round of AV tweaks

Posted by Doug on May 28, 2008

Just when Chase was starting to do some really good stuff with the approximate values I gave him a few weeks ago, I've gone and changed the formula. I doubt that it'll significantly effect any of Chase's results from the previous two posts, but I made a couple of changes that improve the AV formula.

1. In the original formula, the ratio of skill-position AV to offensive line AV was constant from team to team. I discussed this in the very first post about AV. I've now modified that assumption so that teams with more (less) decorated offensive lines, compared to skill position players, will have a higher (lower) percentage of their total AV allotted to the line. To be more specific, an average team has 43.6% of its offensive AV points devoted to linemen. Prior to this change, every team had 43.6% of its offensive AV devoted to linemen. But now, for example, the 1975 Dolphins, who had three pro bowl linemen including two first-team all-pros, and no pro bowl skill position players, will have about 50% of their offensive AV devoted to linemen. Meanwhile, a team like the 1980 Chargers (three first-team all-pros, plus another pro bowler at the skill positions, no pro bowl linemen) will have about 38% of their AV devoted to linemen. These are two of the most extreme examples; the vast majority of teams are very close to the original 43.6%.

Essentially what I'm saying here is that I'm going to trust the writers of the day to tell me whether a given team's offensive success was more due to the line or the skill guys. I'm slightly uneasy with this because I don't completely trust the writers to select pro bowl offensive linemen on their merits, but in the end I'm more comfortable doing it than not doing it.

Likewise, I've made a similar adjustment with respect to dividing the defensive points between front 7 players and defensive backs.

2. I've instituted a minimum AV for first-team all-pros, second-team all-pros, and pro bowlers. We may as well call this the Jonathan Ogden rule, because he's the guy who demonstrated the need for it. The AV formula, because it starts with team success, hates Jon Ogden. Ogden is essentially the opposite of Derrick Brooks, who ranks surprisingly high in AV largely on the basis of being the lone constant on one of the best 12-year team defensive runs of all time. According to my metric of choice --- points per possession --- Ogden has played on a below average offensive team for 11 of his 12 seasons, some of them way below average. As a result, there just haven't been many points to divvy up among the Raven offensive players. So when I run through the formula, Ogden gets a lot of points relative to other Ravens, but still not as many points as he probably should. The AV methodology essentially implies that a terrible offense can't have any great players, and that's not true.

So my inelegant fix is to simply declare that first-team all-pros at tackle and at any defensive position get a minimum of 13 AV no matter what (a typical first-team all-pro gets about 16). Second-team all-pros get a minimum of 11 AV, and pro bowlers get a minimum of 9 AV. At guard, center, and tight end, first-teamers get a minimum of 11, second-teamers 9, and pro bowlers 7. This adjustment really amounts to almost nothing in the grand scheme of things, but it just seems right.

The two adjustments together move Ogden from 153rd on the last AV list I posted to 68th. Willie Roaf, who benefits primarily from the first adjustment, moves from 59th to 41st. You may also note that Marino had a tiny lead on Favre in the last list, and Favre has a tiny lead on Marino in this list. That's because of the first adjustment: Marino played with more decorated linemen than Favre did. Similarly, Walter Payton closes the gap on Faulk and Emmitt Smith.

Here is the current top 200 list:

  1 Reggie White             163
  2 Jerry Rice               159
  3 Brett Favre              147
  4 Bruce Smith              146
    Dan Marino               146
  6 Rod Woodson              142
  7 Lawrence Taylor          139
  8 John Elway               138
  9 Anthony Munoz            137
 10 Peyton Manning           136

I guess I still need this here...

NOTE: the author of the algorithm that generated this list does not agree with the entirety of the list. He, in fact, acknowledges that it’s obviously wrong in spots. He does think it’s pretty respectable, given the difficulty of comparing players across positions and eras using only objective data. He also thinks it’ll give us something to talk about here in May. Also, please read the previous posts.

 11 Steve Young              134
    Derrick Brooks           134
 13 Marshall Faulk           132
 14 Emmitt Smith             128
 15 Walter Payton            127
    Junior Seau              127
 17 Mike Singletary          124
 18 Ray Lewis                123
    Joe Montana              123
 20 Dan Fouts                122
    Jack Youngblood          122
    Barry Sanders            122
 23 Michael Strahan          121
    Ken Anderson             121
    Randy White              121
    Marvin Harrison          121
 27 Bruce Matthews           120
 28 Jack Ham                 119
 29 Warren Moon              118
 30 Ronnie Lott              117
    Warren Sapp              117
 32 Deion Sanders            114
    Chris Doleman            114
    Jack Lambert             114
 35 Zach Thomas              111
    Mel Blount               111
    Thurman Thomas           111
 38 Rickey Jackson           110
    Edgerrin James           110
    Isiah Robertson          110
 41 Willie Roaf              109
    Terrell Owens            109
    Jason Taylor             109
 44 Mike Haynes              108
 45 John Randle              107
    Randy Moss               107
 47 Randall Cunningham       106
    Tony Dorsett             106
    Terry Bradshaw           106
 50 John Hannah              105
    Derrick Thomas           105
    LaDainian Tomlinson      105
    Boomer Esiason           105
    Michael Irvin            105
 55 Tim Brown                104
    Dan Hampton              104
 57 Aeneas Williams          103
    Darrell Green            103
    Randall McDaniel         103
    Drew Bledsoe             103
    Marcus Allen             103
    Steve Largent            103
 63 Mike Webster             102
    Jim Kelly                102
    Ricky Watters            102
    Gary Zimmerman           102
    Rod Smith                102
 68 Franco Harris            101
    James Lofton             101
    Shannon Sharpe           101
    Curtis Martin            101
    Jonathan Ogden           101
 73 Richmond Webb            100
    Steve McMichael          100
    Mike Kenn                100
 76 Tiki Barber               99
    Steve McNair              99
    Sam Mills                 99
    Lemar Parrish             99
 80 Rich Gannon               98
    Cortez Kennedy            98
    Cris Carter               98
    Ronde Barber              98
    Isaac Bruce               98
    Hardy Nickerson           98
    Eric Allen                98
 87 Pat Swilling              97
    Howie Long                97
    Vinny Testaverde          97
    Andre Reed                97
    Richard Dent              97
    Kevin Greene              97
    Dave Krieg                97
    Too Tall Jones            97
 95 Troy Aikman               96
    Mark Brunell              96
    Orlando Pace              96
 98 Henry Ellard              95
    Will Shields              95
    Lomas Brown               95
    John Lynch                95
    Louis Wright              95
103 Jimmy Smith               94
    Neil Smith                94
    Wilber Marshall           94
    Champ Bailey              94
    Ken Stabler               94
    Tony Gonzalez             94
109 Torry Holt                93
    Harry Carson              93
    Trent Green               93
    Clay Matthews             93
    Art Monk                  93
    Roger Craig               93
115 Jackie Slater             92
    Randy Gradishar           92
    Bryant Young              92
    Ray Childress             92
    Brian Urlacher            92
120 Greg Lloyd                91
    Karl Mecklenburg          91
    Tom Brady                 91
    Warrick Dunn              91
    Eric Dickerson            91
    Larry Allen               91
126 John Riggins              90
    Bob Baumhower             90
    Phil Simms                90
    Lyle Alzado               90
    Andre Tippett             90
    Ted Washington            90
    Walter Jones              90
    Steve Grogan              90
    Steve Wisniewski          90
135 Donnie Shell              89
    Jake Scott                89
    Lydell Mitchell           89
    La'Roi Glover             89
139 Cornelius Bennett         88
    Clyde Simmons             88
    Leslie O'Neal             88
    Mo Lewis                  88
143 Brian Dawkins             87
    Tom Jackson               87
    LeRoy Butler              87
    Joe Theismann             87
    Donovan McNabb            87
    Simeon Rice               87
    Jim Everett               87
150 Cliff Branch              86
    Troy Vincent              86
    Willie Anderson           86
    Bruce Armstrong           86
    Dan Dierdorf              86
    Sam Madison               86
    Robert Brazile            86
    Gary Clark                86
158 Joe DeLamielleure         85
    Kevin Carter              85
    Jim Plunkett              85
    Michael Dean Perry        85
    Charles Haley             85
163 Daunte Culpepper          84
    Mike Munchak              84
    Fred Taylor               84
    Eugene Robinson           84
    Tom Nalen                 84
    James Brooks              84
    Jack Reynolds             84
    Cliff Harris              84
171 Joe Jacoby                83
    Keenan McCardell          83
    Ty Law                    83
    Chad Brown                83
    Dermontti Dawson          83
    Henry Thomas              83
    Dave Butz                 83
    Chris Hinton              83
    Fred Smerlas              83
    Carnell Lake              83
181 Priest Holmes             82
    Harvey Martin             82
    Jeff Garcia               82
    Steve Atwater             82
    Tarik Glenn               82
186 Ozzie Newsome             81
    Stanley Morgan            81
    Jim Langer                81
    Kevin Mawae               81
    Ken Norton                81
    Chuck Foreman             81
    Earnest Byner             81
    Bert Jones                81
    Herman Moore              81
    Lee Roy Selmon            81
    Leon Gray                 81
    Charles Mann              81
    Rob Burnett               81
199 Doug Wilkerson            80
    Wes Chandler              80
    Levon Kirkland            80
    John L. Williams          80
    Albert Lewis              80
    Bill Romanowski           80
    Joe Ferguson              80
    Alan Faneca               80
    Nat Moore                 80
    John Stallworth           80
    Harris Barton             80
    Mark Gastineau            80
    Jacob Green               80
    Kellen Winslow            80

This entry was posted on Wednesday, May 28th, 2008 at 4:02 pm and is filed under Approximate Value, General. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.