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ShareThisApproximate value, part III
Here are the links to part I and part II.
Getting approximate values for defensive players proved to be quite a bit tougher than I had anticipated. What I've ended up with is a method that seems pretty sloppy, with lots of arbitrary "add three points for this" and "multiply this times 1.6" sort of rules. But I generally like the results it gives. And since the point of this is not to be theoretically correct, but to build an objective method that matches peoples' subjective opinions, I'm OK with it.
I'm going to do here the opposite of what I did in parts I and II. That is, I'm going to post some lists before posting the complete methodology. The basic idea is the same on the defensive side of the ball as on the offensive: while we don't know the contributions of each individual player, we do know what they should add up to, because we know how good the team was. So I've given each team defense a certain number of points, based on its points allowed per (estimated) possession compared to the league average. And then I've done my best to divvy up those points among those players according to: sacks (post-1982), interceptions, defensive touchdowns, tackles (post-1994), and all-pro status.
As I mentioned above, the exact mix of those ingredients is something I arrived at by trial and error. I've spent a lot of time asking, why does that guy rank so high? Oh, it's because of the way such-and-such a stat gets figured in. That needs fixing. OK, so now why is this other guy so low? Ah, I see, let's tweak that a little.
The main "breakthrough" here, which I've also applied to the offensive linemen, is that, instead of having a binary was-he-or-wasn't-he an all-pro system, I am now using three different degrees of all-pro-ness: first-team AP all-pro, second-team AP all-pro, and pro bowler who didn't make the first- or second-team all-pro list. This helps to separate the Kevin Williamses from the Trent Coles. Not that there's anything wrong with Trent Cole, but he's no Kevin Williams.
Enough chit-chat. I'm just going to post my approximate value estimates for a handful of famous teams and a few '07 teams. The number immediately after each player is my approximate value estimate. The second number, which is either a 1, 2, or 3, signifies the level of all-pro-ness of that player for that year. 1=first team, 2=second team, 3=pro bowler not on first or second team. But note that this information is only figured into the system at the non-skill positions, where I feel like we don't have the stats necessary to give them reasonable ratings without it. In other words, I'm comfortable (approximately) rating Derek Anderson and Franco Harris and Wesley Walker without knowing whether or not they made the pro bowl in a given year, but I'm not comfortable rating Jeff Saturday or Dave Duerson or Terrence Newman.
Peruse the lists and let me know what sticks out. Who's way off? Do you see anything that appears to you to be a systematic error?
2007 Patriots Tom Brady 26 1 Randy Moss 21 1 Matt Light 21 1 Wes Welker 17 2 Mike Vrabel 15 1 Vince Wilfork 13 2 Logan Mankins 13 2 Asante Samuel 13 1 Dan Koppen 12 2 Laurence Maroney 10 Nick Kaczur 10 Donte Stallworth 10 Ty Warren 8 Kevin Faulk 8 Ellis Hobbs 8 Adalius Thomas 8 Tedy Bruschi 7 Ben Watson 7 James Sanders 6 Rosevelt Colvin 6 Jabar Gaffney 6 Jarvis Green 6 Russ Hochstein 5 Junior Seau 4 Rodney Harrison 4 Richard Seymour 4 Steve Neal 4 Sammy Morris 4 Kyle Brady 3 Randall Gay 3 Eugene Wilson 3 Heath Evans 3 Willie Andrews 2 Ryan O'Callaghan 2 Kyle Eckel 1 Lonie Paxton 1 Brandon Meriweather 1 Corey Mays 1 LeKevin Smith 1 Mike Wright 1 Billy Yates 1 Eric Alexander 1 Pierre Woods 1 Mel Mitchell 1 Larry Izzo 1 Wesley Britt 1 2000 Ravens Ray Lewis 23 1 Rob Burnett 20 2 Rod Woodson 19 2 Sam Adams 17 2 Michael McCrary 12 Jamal Lewis 12 Jonathan Ogden 12 1 Jamie Sharper 11 Chris McAlister 11 Peter Boulware 10 Duane Starks 10 Kim Herring 10 Tony Siragusa 9 Shannon Sharpe 9 Qadry Ismail 7 Priest Holmes 6 Tony Banks 5 Edwin Mulitalo 5 Harry Swayne 5 Mike Flynn 5 Trent Dilfer 5 Jeff Mitchell 4 Jermaine Lewis 4 Travis Taylor 3 Spencer Folau 2 Patrick Johnson 2 O.J. Brigance 2 James Trapp 2 Cornell Brown 2 Brad Jackson 2 Lional Dalton 2 Corey Harris 2 Obafemi Ayanbadejo 2 Robert Bailey 2 Brandon Stokley 2 Ben Coates 2 Anthony Mitchell 2 Keith Washington 2 Anthony Poindexter 1 Billy Davis 1 Sam Gash 1 Kipp Vickers 1 Larry Webster 1 Anthony Davis 1 1999 Rams Marshall Faulk 25 1 Kurt Warner 20 1 Kevin Carter 19 1 Orlando Pace 19 1 Isaac Bruce 14 2 Todd Lyght 14 2 Mike Jones 11 Grant Wistrom 11 Fred Miller 10 D'Marco Farr 9 London Fletcher 9 Torry Holt 9 Az-Zahir Hakim 9 Ray Agnew 8 Mike Gruttadauria 8 Adam Timmerman 8 Billy Jenkins 7 Todd F. Collins 7 Tom Nutten 7 Dexter McCleon 7 Devin Bush 5 Robert Holcombe 4 Ricky Proehl 4 Keith Lyle 4 Roland Williams 4 Jeff Robinson 3 Dre' Bly 3 Jeff Zgonina 3 Charlie Clemons 2 Jay Williams 2 James Hodgins 2 Chad Lewis 2 Lorenzo Styles 2 Tony Horne 2 2 Taje Allen 2 Andy McCollum 2 Ron Carpenter 1 Justin Watson 1 Rich Coady 1 Mike Morton 1 Nate Hobgood-Chittick 1 Joe Germaine 1 Troy Pelshak 1 Ryan Tucker 1 1978 Steelers Terry Bradshaw 16 1 Jack Ham 15 1 Mike Webster 14 1 Joe Greene 13 3 Jack Lambert 12 3 Donnie Shell 12 3 Lynn Swann 12 1 Mel Blount 11 2 Franco Harris 11 3 John Stallworth 11 L.C. Greenwood 10 3 Jon Kolb 10 John Banaszak 9 Ron Johnson 8 Randy Grossman 8 Rocky Bleier 8 Dwight White 7 Ray Pinney 7 Sam Davis 7 Mike Wagner 7 Gerry Mullins 7 Loren Toews 6 Bennie Cunningham 5 Robin Cole 5 Steve Furness 4 Sidney Thornton 3 Larry Anderson 3 Larry Brown 3 Tony Dungy 3 Steve Courson 2 Fred Anderson 2 Tom Beasley 2 Dirt Winston 2 Gary Dunn 2 Nat Terry 1 Rick Moser 1 Theo Bell 1 Jim Smith 1 Ted Petersen 1 Wentford Gaines 1 Jim Mandich 1 1985 Bears Walter Payton 19 1 Richard Dent 18 1 Mike Singletary 17 1 Steve McMichael 16 1 Gary Fencik 16 2 Jimbo Covert 16 1 Otis Wilson 15 2 Dan Hampton 14 2 Jim McMahon 13 3 Dave Duerson 12 3 Willie Gault 10 Leslie Frazier 9 Jay Hilgenberg 9 3 Keith Van Horne 9 Mike Richardson 9 Emery Moorehead 7 Wilber Marshall 7 Matt Suhey 7 Mark Bortz 7 Dennis McKinnon 7 Tim Wrightman 6 Tom Thayer 6 William Perry 5 Mike Hartenstine 4 Steve Fuller 4 Dennis Gentry 3 Calvin Thomas 2 Ron Rivera 2 Reggie Phillips 2 Ken Taylor 2 Andy Frederick 2 Cliff Thrift 2 Shaun Gayle 2 Ken Margerum 2 Tom Andrews 1 Jim Morrissey 1 Tyrone Keys 1 Thomas Sanders 1 Henry Waechter 1 Stefan Humphries 1 Kurt Becker 1 1990 Bills Thurman Thomas 19 1 Bruce Smith 15 1 Jim Kelly 15 3 Andre Reed 13 2 Kent Hull 13 1 Will Wolford 11 3 Shane Conlan 11 2 Darryl Talley 10 3 Cornelius Bennett 10 3 James Lofton 10 Nate Odomes 9 Howard Ballard 9 Keith McKeller 8 Leonard Smith 8 John H. Davis 7 Jeff Wright 7 Leon Seals 7 Jim Ritcher 7 John Hagy 5 Kirby Jackson 5 Don Smith 4 Ray Bentley 4 Kenneth Davis 4 Carlton Bailey 3 Don Beebe 3 Jamie Mueller 3 James E. Williams 3 Pete Metzelaars 2 Mark Kelso 2 Frank Reich 2 Glenn Parker 2 Marvcus Patton 1 Dwight Drane 1 Gary Baldinger 1 Chris Hale 1 Mike Lodish 1 Hal Garner 1 Steve Tasker 1 3 Jeff Hunter 1 Mark Pike 1 Butch Rolle 1 David Pool 1 Carwell Gardner 1 Adam Lingner 1 Mitch Frerotte 1 2007 Giants Osi Umenyiora 12 3 Eli Manning 11 Plaxico Burress 10 Brandon Jacobs 9 Kareem McKenzie 9 Kawika Mitchell 9 Antonio Pierce 8 Jeremy Shockey 8 Amani Toomer 8 Michael Strahan 8 Rich Seubert 7 Sam Madison 7 Chris Snee 7 David Diehl 7 Shaun O'Hara 7 Fred Robbins 7 Barry Cofield 7 Gibril Wilson 6 Derrick Ward 6 James Butler 5 Aaron Ross 5 Mathias Kiwanuka 5 Justin Tuck 4 Michael Johnson 3 Kevin Dockery 3 Corey Webster 3 Reggie Torbor 3 Kevin Boss 2 Chase Blackburn 2 Reuben Droughns 2 Michael Matthews 2 Sinorice Moss 2 Madison Hedgecock 2 R.W. McQuarters 2 Craig Dahl 1 Guy Whimper 1 Grey Ruegamer 1 Steve 2. Smith 1 Gerris Wilkinson 1 Russell Davis 1 Zak DeOssie 1 Jay Alford 1 Domenik Hixon 1 Ahmad Bradshaw 1 2007 49ers Patrick Willis 17 1 Frank Gore 10 Marques Douglas 8 Bryant Young 8 Mark Roman 8 Nate Clements 7 Michael Lewis 7 Derek Smith 7 Aubrayo Franklin 6 Tully Banta-Cain 6 Walt Harris 6 Parys Haralson 6 Arnaz Battle 5 Vernon Davis 5 Joe Staley 5 Eric Heitmann 4 Darrell Jackson 4 Adam Snyder 4 Larry Allen 4 Isaac Sopoaga 3 Donald Strickland 2 Justin Smiley 2 Jonas Jennings 2 Jeff Ulbrich 2 David Baas 2 Brandon T. Moore 2 Keith Lewis 1 Zak Keasey 1 Moran Norris 1 Hannibal Navies 1 Manny Lawson 1 Dashon Goldson 1 Ray McDonald 1 Shaun Hill 1 Brian Jennings 1 Bryan Gilmore 1 Roderick Green 1 Ashley Lelie 1 Tarell Brown 1 Ronald Fields 1 Shawntae Spencer 1 Billy Bajema 1 Maurice Hicks 1 Michael Robinson 1 Marcus Hudson 1 Delanie Walker 1 2007 Browns Derek Anderson 15 3 Braylon Edwards 13 2 Kellen Jr. Winslow 13 3 Jamal Lewis 12 Joe Thomas 10 3 Robaire Smith 8 Kevin Shaffer 8 Kamerion Wimbley 7 Leigh Bodden 6 Shaun Smith 6 Joe Jurevicius 6 Sean Jones 6 D'Qwell Jackson 6 Hank Fraley 6 Eric Steinbach 6 Brodney Pool 6 Willie McGinest 5 Leon Williams 5 Eric Wright 5 Andra Davis 5 Josh Cribbs 4 2 Ryan Tucker 4 Jason Wright 4 Lawrence Vickers 4 Antwan Peek 3 Daven Holly 3 Ethan Kelley 3 Seth McKinney 3 Orpheus Roye 3 Brandon McDonald 2 Simon Fraser 2 Steve Heiden 2 Mike Adams 1 Lennie Friedman 1 David McMillan 1 Chaun Thompson 1 Ted Washington 1 Ryan Pontbriand 1 3 Nick Sorensen 1 Jerome Harrison 1 Kris Griffin 1 Tim Carter 1 Kenny Wright 1 Darnell Dinkins 1
This entry was posted on Thursday, April 10th, 2008 at 9:45 am 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.
I take it that there is more to come on this subject?
An ambitious project to be sure. I've skimmed all three parts and can't claim to fully grasp the methodology. But since you asked, and since I'm a Browns fan, a 4 for Josh Cribbs is just way, way too low.
And whatever method that caused Shaffer to get 8 compared to Steinbach's 6 needs tweaking.
The defensive players seem fairly well assessed.
Keep at it!
As a niners fan, I can say that the defense appears to be getting too much credit compared to other teams, simply since the defense was on the field so much of every game. Mark Roman is NOT a good safety; I just can't imagine him being rated that high.
Interior lineman who focus on run-stopping and taking on multiple lineman (the 'big ol' nose tackle' position) don't get as much credit as they ought to, either.
The Giants defensive line looks underestimated in this system, too.
One more thought: Fullbacks don't get any credit, I think. Moran Norris is one of the better blocking fullbacks in the league, but gets only one point. Zak Keasey, who was on the practice squad nearly the entire season and has only touched the ball twice in his life, got a point too.
I'd have to agree that most of this looks pretty good. The one that stood out the most to me was a 4 for Justin Tuck, who looked downright dominant an awful lot last year. It's not his fault Strahan and Umenyiora are on his team, too.
Jiffy, I was going to say the same thing. Maybe we need an adjustment. How about calling it the "Tuck Rule"
One more thought: Fullbacks don’t get any
credit, I think.
Yeah, neither do blocking TEs, like Kyle Brady. I think this system is pretty good, though. The numbers match my intuitions fairly well for the most part, and there's no obvious solution for guys that have a role on the team that isn't measured well by stats.
Doug, the only thing that troubles me about this system is how the QB/WR credit is divided for the passing game.
For the 2007 Patriots: Brady, Welker, and Moss combine for 64 points of value. I think you could make a great argument for the 07 Pats having the greatest air attack of all time, but 64 points seems like you are giving them too much credit.
The '99 Rams, by the same system, only score 52 points if you total Warner, Bruce, Holt, AND the third WR, Az Hakim.
My only recommendation would be to throw in an adjustment that docks receivers some value if they are playing with an All Pro QB. If Moss' total comes down to around 16-17, and Welker's to 14-15, I feel that would be more in line with their total contribution to the 07 Pats.
After all, those values would still make each of them the most valuable player on the SB Champion Giants
Thanks to all for the comments. I basically agree with all of them but don't know if anything can be done about any of them.
To Greg (8): Three things. The Pats were, according to my metric, quite a bit better than the 99 Rams on offense, and they were more pass-oriented also. Plus, about 9 or 10 of Marshall Faulk's points were from receiving. Those things add up to the difference you see.
All the other issues are basically caused by the fact that stat lines just don't tell us much about some guys.
Shaffer and Steinbach, for example, have identical stat lines (16 G, 16 GS). Since Shaffer is a tackle and, all else equal, tackles are perceived as being more important than guards, Shaffer rates a couple of points higher than Steinbach.
With regard to the blocking fullbacks and TEs, I wrote this in the second post (linked at the top):
I don't disagree that certain guys are going to get unfairly rated because of this, but I don't know if anything can be done about it.
Did Alex Smith really draw a 0 this year? That's pretty funny.
That was my question too. Dilfer and Smith both sucked but they started several games. Did they get zeroed out because Hill ended the season as a starter, or was their value actually zero?
Regarding the 49ers defensive players numbers being a bit elevated because they were on the field all the time, that doesn't really seem wrong to me. Because they were on the field most of the time, their value should be higher. It's not measuring skill, just value. Steve Young would have values of close to zero in those years where he only played a game or two behind Montana.
I may have missed it somewhere, but is special teams taken into account at all? Welker was a kick and punt returner, etc. Or, would Hester even show up as a blip on the radar for the 05 Bears?
Err, 06 Bears
Most of the players who I was going "hang on" over were left tackles (Light far too high, Ogden and Joe Thomas too low). I suspect that it may also be an issue with quarterback play impacting the measurable aspects of line play. Light looks better than he was to the system (assuming the line gets debited for sacks) because Brady gets rid of the ball so quickly. Ogden was blocking for Trent Dilfer. Obviously this will affect other positions on the line too, but if the left tackle gets the highest proportion of line credits, he will be the man most affected. Some sort of second order adjustment to other offensive players for quarterback quality might be required.
Also, I think WR1 and WR2 should be treated as different positions. Welker comes out far too valuable, to my mind. Partly the selectors' fault for making him all-pro when he shouldn't have been, of course.
I think a great way to test to see if the metric is valid would be to use it to determine how good all the different GM's are at drafting. You could compare the value of each pick of each GM's draft to the avereage value recieved for each pick. Then if the GM's we all know were the best show up as the best it validates the aproximate value as a metric. I would love to see these numbers each year at draft time just to see what the average AV for each draft position my team is selecting from.
The thing that I notice is unless the defensive players are All Pro or played in the Pro Bowl, they are basically perpetually inferior to the Offensive guys. But that is a small issue, IMO. Love this method of comparing players.