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Archive for August, 2008

38 questions: a p-f-r blog contest

Posted by Doug on August 30, 2008

Below you will find 38 pairs of numbers. In each case, you tell me which number will be bigger. One point for each correct answer. Most points wins.

Ties --- and I expect there to be a nontrivial number of them --- go to the side that had fewer votes. For example, here is a pair:

Number of wins by the Lions
Number of wins by the Ravens

Let's say 41 people take the Lions and 54 take the Ravens. If the Lions and Ravens end up with the same number of wins, then each Lion-backer will get a point and each Raven-backer will not.

GRAND PRIZE: the main prizes will be (1) honor and (2) glory. There will also be some sort of trinket to be named later. Maybe a shirt, or a football book of some sort. By the time this thing is over, more than five months will have passed, so that gives me some time to scrape something together. But you probably shouldn't enter unless honor and glory are sufficient.

MORE RULES:

1. Everyone is limited to one entry per person. This will be enforced by the honor system. If caught breaking this rule, you, your children, and your children’s children will be banned from all future p-f-r contests. For three months*.

2. I won’t enter the contest myself, which will allow me to arbitrate any dispute impartially. Any ambiguities in the rules will be clarified by me in whatever way causes me the least amount of hassle.

3. While there are quite a few items that refer in some way to the NFL postseason, unless specifically stated, all the items below refer to regular season totals only. For example, here's a pair:

Margin of the Chiefs biggest win.
Number of Rushing TDs scored by (the Vikings') Adrian Peterson

This one will be decided based on the Chiefs regular season and Adrian Peterson's regular season numbers. I'd hate for there to be confusion when the Chiefs win a playoff game by 28.

4. If you try to get cute and complain that the Chiefs one-point win over the Raiders was actually their "biggest win" even though it wasn't their win with the biggest point margin, see rule #2. Deleting your email on sight is generally my hassle-minimization strategy of choice.

5. You may enter until 1:00 p.m. Eastern time on Sunday, September 7th, 2008. However, you can earn a bonus of two (2) points if you enter before kickoff of Thursday's game.

6. In the event that the contest ends in a tie, the winner will be the person whose entry was submitted first.

7. HOW TO ENTER: cut-and-paste the list of questions below into your editor of choice, delete the choices you don't like (thereby leaving the ones you do like), and then cut-and-paste your 38 answers into the comments of this thread. Please do not edit the text in any way other than deleting half of it.

The 38 questions:

65 Comments | Posted in P-F-R News

AV all-franchise teams redux: AFC

Posted by Doug on August 29, 2008

Just for fun, I decided to use my Approximate Value method to come up with a post-merger all-franchise team for each franchise.

Throughout the dog days, I had been posting these by division, and I had been limiting these lists to post-merger players. But after six divisions were done, I revamped the AV formula to include seasons in the 1950--1969 range. So I'm going to post all the teams in two posts. This one is the AFC edition.

Here are the rules:

1. The AV systems gives a player a score for each player season. To combine these into a career number, I take 100% of the player’s best season, plus 95% of his second-best season, plus 90% of his third-best season, and so on.

2. I’m only comfortable (for now) applying the AV methodology to seasons 1950 and later. Players who debuted before 1950, however, are included if their post-1950 seasons alone merit inclusion. In this case, they have a ‘+’ after their AV score to remind you that their career AV is (probably) higher than the number shown.

3. To avoid 4-3/3-4/5-2 issues, I gave each defense 12 players, including two DT/NTs, two DEs, two OLBs, and two ILB/MLBs. I have also now lumped all safeties together instead of distinguishing between free and strong safeties.

4. Because of the slippery and changing nature of defining what a fullback is, I simply decided to go with two RB/FBs, instead of an RB and an FB.

5. What to do with players whose position was "End" in the 50s. Are they tight ends? Wide receivers? To deal with this problem, I've lumped TEs, WRs, and Es of all years into one category, which I've called 'RC' (ReCeiver), and I'm allowing four of them per team. After all, if the defense is playing with 12, I should allow the offense the same luxury.

As with most things AV-related, this series of posts is mostly just for fun, but I’m also curious to hear feedback from long-time followers of the teams about things that look fishy.

EDIT: commenter Scott uncovered a bug in my program. These lists were updated to correct the error on the morning of Sunday, 8/31. Thanks, Scott!

Baltimore Ravens

QB   Vinny Testaverde      24
RB   Jamal Lewis           54
RB   Priest Holmes         17
RC   Todd Heap             39
RC   Travis Taylor         24
RC   Qadry Ismail          22
RC   Michael Jackson       22
T    Jonathan Ogden       101
T    Orlando Brown         30
G    Edwin Mulitalo        27
G    Jeff Blackshear       21
C    Mike Flynn            32

DT   Kelly Gregg           47
DT   Tony Siragusa         33
DE   Rob Burnett           48
DE   Michael McCrary       47
ILB  Ray Lewis            123
ILB  Ed Hartwell           26
OLB  Peter Boulware        60
OLB  Adalius Thomas        52
CB   Chris McAlister       72
CB   Duane Starks          23
S    Ed Reed               61
S    Rod Woodson           45

Buffalo Bills

QB   Jim Kelly            102
RB   Thurman Thomas       110
RB   O.J. Simpson          91
RC   Andre Reed            96
RC   Eric Moulds           69
RC   Bob Chandler          42
RC   Frank Lewis           40
T    Joe Devlin            60
T    Ken Jones             50
G    Joe DeLamielleure     63
G    Ruben Brown           63
C    Kent Hull             73

DT   Fred Smerlas          81
DT   Jim Dunaway           55
DE   Bruce Smith          139
DE   Phil Hansen           63
ILB  Shane Conlan          50
ILB  Jim Haslett           41
OLB  Mike Stratton         71
OLB  Cornelius Bennett     71
CB   Butch Byrd            58
CB   Charles Romes         54
S    Henry Jones           57
S    George Saimes         56

Cincinnati Bengals

QB   Ken Anderson         121
RB   James Brooks          71
RB   Corey Dillon          54
RC   Chad Johnson          73
RC   Isaac Curtis          67
RC   Cris Collinsworth     65
RC   Bob Trumpy            64
T    Anthony Munoz        137
T    Willie Anderson       86
G    Max Montoya           64
G    Dave Lapham           46
C    Bob Johnson           57

DT   Tim Krumrie           65
DT   Mike Reid             47
DE   Eddie Edwards         61
DE   Ross Browner          51
ILB  Jim LeClair           59
ILB  Glenn Cameron         45
OLB  Reggie Williams       74
OLB  Al Beauchamp          51
CB   Ken Riley             91
CB   Lemar Parrish         77
S    David Fulcher         52
S    Tommy Casanova        49

Cleveland Browns

QB   Otto Graham           83+
RB   Jim Brown            105
RB   Leroy Kelly           74
RC   Ozzie Newsome         81
RC   Milt Morin            57
RC   Gary Collins          53
RC   Paul Warfield         52
T    Lou Groza             99+
T    Dick Schafrath        98
G    Gene Hickerson        92
G    Jim Ray Smith         65
C    Frank Gatski          68+

DT   Bob Gain              78
DT   Michael Dean Perry    71
DE   Len Ford              96+
DE   Bill Glass            58
ILB  Vince Costello        56
ILB  Mike Johnson          47
OLB  Clay Matthews         90
OLB  Walt Michaels         79
CB   Hanford Dixon         68
CB   Frank Minnifield      64
S    Thom Darden           55
S    Ken Konz              46

Denver Broncos

QB   John Elway           138
RB   Terrell Davis         73
RB   Floyd Little          71
RC   Rod Smith            102
RC   Shannon Sharpe        92
RC   Riley Odoms           76
RC   Ed McCaffrey          58
T    Ken Lanier            62
T    Matt Lepsis           62
G    Paul Howard           48
G    Dan Neil              42
C    Tom Nalen             84

DT   Rubin Carter          74
DT   Trevor Pryce          65
DE   Barney Chavous        73
DE   Rulon Jones           64
ILB  Randy Gradishar       92
ILB  Karl Mecklenburg      91
OLB  Tom Jackson           87
OLB  Simon Fletcher        62
CB   Louis Wright          95
CB   Champ Bailey          54
S    Bill Thompson         86
S    Steve Atwater         79

Houston Texans

QB   David Carr            41
RB   Domanick Williams     32
RB   Ron Dayne             10
RC   Andre Johnson         41
RC   Jabar Gaffney         16
RC   Corey Bradford        14
RC   Owen Daniels          14
T    Ephraim Salaam        13
T    Eric Winston          10
G    Chester Pitts         33
G    Zach Wiegert          15
C    Steve McKinney        20

DT   Seth Payne            20
DT   Travis Johnson         9
DE   Gary Walker           22
DE   Jerry DeLoach         18
ILB  Jamie Sharper         25
ILB  Jay Foreman           21
OLB  Kailee Wong           24
OLB  Morlon Greenwood      17
CB   Aaron Glenn           21
CB   Dunta Robinson        19
S    C.C. Brown            14
S    Eric Brown            13

Indianapolis Colts

QB   Johnny Unitas        141
RB   Edgerrin James        99
RB   Lenny Moore           95
RC   Marvin Harrison      121
RC   Raymond Berry        101
RC   John Mackey           76
RC   Reggie Wayne          75
T    Jim Parker           101
T    Tarik Glenn           82
G    Alex Sandusky         68
G    Art Spinney           59
C    Jeff Saturday         73

DT   Art Donovan           81
DT   Fred Miller           78
DE   Gino Marchetti       119
DE   Ordell Braase         74
ILB  Mike Curtis           82
ILB  Jeff Herrod           45
OLB  Don Shinnick          67
OLB  Bill Pellington       64
CB   Bobby Boyd            91
CB   Eugene Daniel         58
S    Jerry Logan           70
S    Rick Volk             70

Jacksonville Jaguars

QB   Mark Brunell          86
RB   Fred Taylor           84
RB   James Stewart         25
RC   Jimmy Smith           94
RC   Keenan McCardell      55
RC   Kyle Brady            33
RC   Pete Mitchell         27
T    Tony Boselli          63
T    Maurice Williams      42
G    Chris Naeole          33
G    Vince Manuwai         30
C    Brad Meester          42

DT   John Henderson        55
DT   Marcus Stroud         51
DE   Tony Brackens         49
DE   Paul Spicer           32
ILB  Mike Peterson         38
ILB  Bryan Schwartz        18
OLB  Kevin Hardy           46
OLB  Daryl Smith           31
CB   Rashean Mathis        45
CB   Aaron Beasley         30
S    Donovin Darius        44
S    Deon Grant            21

Kansas City Chiefs

QB   Len Dawson            98
RB   Priest Holmes         69
RB   Ed Podolak            54
RC   Tony Gonzalez         94
RC   Fred Arbanas          66
RC   Otis Taylor           65
RC   Henry Marshall        53
T    Jim Tyrer             95
T    John Alt              68
G    Will Shields          95
G    Ed Budde              77
C    Jack Rudnay           62

DT   Buck Buchanan        101
DT   Dan Saleaumua         57
DE   Neil Smith            80
DE   Jerry Mays            80
ILB  Willie Lanier         98
ILB  Sherrill Headrick     52
OLB  Derrick Thomas       105
OLB  Bobby Bell           105
CB   Emmitt Thomas         78
CB   Albert Lewis          69
S    Johnny Robinson       92
S    Deron Cherry          78

Miami Dolphins

QB   Dan Marino           146
RB   Larry Csonka          65
RB   Tony Nathan           59
RC   Nat Moore             80
RC   Mark Duper            76
RC   Mark Clayton          75
RC   Paul Warfield         55
T    Richmond Webb         97
T    Norm Evans            66
G    Larry Little          98
G    Bob Kuechenberg       77
C    Jim Langer            80

DT   Bob Baumhower         90
DT   Tim Bowens            63
DE   Jason Taylor         109
DE   Bill Stanfill         77
ILB  Zach Thomas          111
ILB  Nick Buoniconti       62
OLB  Larry Gordon          51
OLB  Doug Swift            47
CB   Sam Madison           79
CB   Curtis Johnson        55
S    Jake Scott            72
S    Dick Anderson         70

New England Patriots

QB   Tom Brady             91
RB   Sam Cunningham        60
RB   Tony Collins          47
RC   Stanley Morgan        80
RC   Ben Coates            58
RC   Troy Brown            54
RC   Russ Francis          48
T    Bruce Armstrong       86
T    Matt Light            59
G    John Hannah          105
G    Sam Adams             44
C    Jon Morris            60

DT   Houston Antwine       66
DT   Ray Hamilton          53
DE   Willie McGinest       71
DE   Richard Seymour       69
ILB  Steve Nelson          70
ILB  Tedy Bruschi          66
OLB  Andre Tippett         90
OLB  Chris Slade           51
CB   Raymond Clayborn      75
CB   Mike Haynes           73
S    Lawyer Milloy         56
S    Fred Marion           49

New York Jets

QB   Joe Namath            88
RB   Curtis Martin         79
RB   Freeman McNeil        78
RC   Wesley Walker         72
RC   Don Maynard           69
RC   Jerome Barkum         62
RC   Rich Caster           61
T    Winston Hill          79
T    Marvin Powell         78
G    Randy Rasmussen       67
G    Dan Alexander         60
C    Joe Fields            68

DT   Joe Klecko            71
DT   Marty Lyons           50
DE   Mark Gastineau        80
DE   Gerry Philbin         60
ILB  Kyle Clifton          56
ILB  Marvin Jones          52
OLB  Mo Lewis              88
OLB  Larry Grantham        87
CB   Aaron Glenn           53
CB   James Hasty           42
S    Victor Green          47
S    Burgess Owens         36

Oakland Raiders

QB   Ken Stabler           79
RB   Marcus Allen          87
RB   Mark van Eeghen       60
RC   Tim Brown            103
RC   Cliff Branch          86
RC   Fred Biletnikoff      85
RC   Todd Christensen      64
T    Art Shell            103
T    Henry Lawrence        66
G    Gene Upshaw          110
G    Steve Wisniewski      90
C    Jim Otto              99

DT   Otis Sistrunk         59
DT   Chester McGlockton    54
DE   Howie Long            97
DE   Ben Davidson          58
ILB  Dan Conners           72
ILB  Matt Millen           54
OLB  Ted Hendricks         75
OLB  Rod Martin            74
CB   Willie Brown         104
CB   Lester Hayes          72
S    George Atkinson       64
S    Jack Tatum            63

Pittsburgh Steelers

QB   Terry Bradshaw       106
RB   Franco Harris        101
RB   Jerome Bettis         65
RC   John Stallworth       80
RC   Hines Ward            72
RC   Lynn Swann            61
RC   Louis Lipps           55
T    Larry Brown           68
T    Jon Kolb              67
G    Alan Faneca           80
G    Sam Davis             49
C    Mike Webster         100

DT   Joe Greene           126
DT   Ernie Stautner       111
DE   L.C. Greenwood        95
DE   Dwight White          65
ILB  Jack Lambert         114
ILB  Levon Kirkland        71
OLB  Jack Ham             119
OLB  Greg Lloyd            89
CB   Mel Blount           111
CB   Rod Woodson          104
S    Donnie Shell          89
S    Carnell Lake          73

San Diego Chargers

QB   Dan Fouts            122
RB   LaDainian Tomlinson  105
RB   Chuck Muncie          41
RC   Kellen Winslow        80
RC   Charlie Joiner        78
RC   Lance Alworth         73
RC   Gary Garrison         60
T    Russ Washington       99
T    Ron Mix               75
G    Doug Wilkerson        80
G    Walt Sweeney          76
C    Don Macek             55

DT   Gary Johnson          69
DT   Jamal Williams        59
DE   Leslie O'Neal         72
DE   Fred Dean             56
ILB  Gary Plummer          42
ILB  Donnie Edwards        41
OLB  Junior Seau          120
OLB  Woodrow Lowe          56
CB   Gill Byrd             60
CB   Mike H. Williams      42
S    Kenny Graham          49
S    Rodney Harrison       46

Tennessee Titans

QB   Warren Moon           97
RB   Eddie George          75
RB   Earl Campbell         63
RC   Ken Burrough          65
RC   Ernest Givins         63
RC   Drew Hill             60
RC   Frank Wycheck         58
T    Brad Hopkins          72
T    Walt Suggs            49
G    Bruce Matthews       120
G    Mike Munchak          84
C    Carl Mauck            32

DT   Ray Childress         92
DT   Curley Culp           59
DE   Elvin Bethea          88
DE   Pat Holmes            50
ILB  Gregg Bingham         65
ILB  Al Smith              54
OLB  Robert Brazile        86
OLB  Keith Bulluck         56
CB   Cris Dishman          52
CB   Zeke Moore            51
S    Blaine Bishop         57
S    Marcus Robertson      53

16 Comments | Posted in Approximate Value, General

Fantasy Running Backs and Team Passing Efficiency

Posted by Jason Lisk on August 27, 2008

How important is a good passing game to a running back for fantasy football purposes? Do you want the guy that is a cog in a good offense, or the guy that is the offense?

To check how important the team's passing game is on the fantasy production of the running back, I went through the last twenty years (1988-2007) and found every running back who finished at least 80 fantasy points over baseline (where baseline equals the 24th highest scoring back) in a non-point per reception league (1 point for every 10 rushing and receiving yards; 6 points per touchdown). That produced 138 running back seasons--an average of 6.9 per season. While there has been fluctuation from season to season regarding how many backs have reached that benchmark, from a low of three (1990-1991) to a high of nine (1989, 1998, 2000, 2002 & 2003), I think it is a pretty good measuring stick for elite running backs in a given season.

I then took that list of 138 players and found the team rank in the season in question in adjusted net passing yards per attempt (ANYPA). ANYPA incorporates both sacks and interceptions into the efficiency number. For the purposes of this post, it does a good job of measuring how efficient a passing offense was in creating opportunities for the running back, as a team with a decent yards per attempt, but high interception and sack totals, is going to take the ball out of the hands of the running back by surrendering possession or placing the team in poor running situations.

Once I found the ANYPA rank for each team that had a running back finish with at least 80 fantasy points over baseline, I sorted those backs into tiers based on their relative ranking, and the league size at the time (since there were 28 teams in 1988, but 32 now). The top three passing offenses by ANYPA are tier 1 in the chart below. Each subsequent tier represents approximately the next 10th percentile (rounded to the nearest whole number).

Before getting to the charts, however, I guess I should point out that I'm not making value judgments about the specific quarterbacks that were on these teams; I'm only going by the end result of passing rank. In some situations, the back may be influencing the team passing efficiency numbers by allowing big plays in the passing game due to team's overplaying to stop the back, in others, the back may be the beneficiary of a great offensive cast. In many cases, it's probably a little of both. For example, if I told you that Terry Allen finished first in fantasy points in 1996 with Gus Frerotte as his quarterback, and Ricky Watters finished third with Ty Detmer at quarterback, your gut reaction, without going back and looking at the numbers, is probably that they didn't have very good passing teams. By the numbers, though, Washington was actually the #1 team in ANYPA in 1996, and Philadelphia ranked #11. Let's go ahead and get the first chart, showing how many backs played for a team that had a passing offense in each tier, and how many fantasy points the top backs in each tier averaged:

19 Comments | Posted in Fantasy, General

Usain Bolt and NFL combine 40 times

Posted by Doug on August 21, 2008

Let me preface this by saying that almost every single word of what I'm about to write could potentially be incorrect. I don't really know what I'm talking about. Possibly the most reliable source I've used here is Wikipedia, if that tells you anything.

But you guys will help correct me if I say something really stupid, right?

It all starts with a message board post from a guy I don't know that I saw linked from another message board.

Usain Bolt's splits during the Olympic 100m race

RT 0.165
10m 1.85
20m 2.87 (1.02)
30m 3.78 (0.91)
40m 4.65 (0.87)
50m 5.50 (0.85)
60m 6.32 (0.82)
70m 7.14 (0.82)
80m 7.96 (0.82)
90m 8.79 (0.83)
100m 9.69 (0.90)

30m is 32.8084 yards. So he needs to cover 7.1916 more yards from there.

He ran from 30m to 40m in .87 seconds, or .087 seconds per meter, or .0795528 seconds per yard. But he wasn't at top speed yet. So the first 7 yards of that would have been slightly slower than the average of the full ten meters, but faster than the .0832 seconds per yard at which he ran from meter 20 to meter 30. So let's say he averaged a nice round .08 seconds per yard. Multiply that by 7.1916 and you get .575. Add that to his 30m split and you're at 4.35 or 4.36.

So unless I've done something wrong, we have the following:

At 40 yards of the actual Olympic 100m race, Bolt was at 4.35 or 4.36

But wait...

His reaction time was .165. My understanding is that the combine 40 is timed from the runner's actual start rather than from a gun. So if this were in an NFL combine setting, that reaction time would be gone and he'd be at 4.19.

But wait...

There are no starting blocks at the NFL combine. And my understanding is that this particular Olympic track is the fastest around. Those two things would push his NFL combine time up over 4.2, maybe up to 4.25 or even 4.3.

But wait...

If he were training specifically for the 40, he might be able to do some things somewhat differently to shave a few hundredths off.

I hereby declare that Bolt would run a 4.22 at the combine.

Chris Johnson ran a 4.24 at this year's combine. Does that make my Bolt estimate seem too high? Or does it mean that the timing at the combine is inexact or inconsistent or just plain generous? Could be either one --- or both --- but I'm not totally sure the two figures are incompatible. It was around the halfway point that Bolt really blew everyone else away; I don't even think he was leading at 40 yards. So it's not clear to me that Chris Johnson couldn't hang close to him for 40 yards.

59 Comments | Posted in NFL Draft, Non-football

What’s a starting QB worth? Part III

Posted by Doug on August 20, 2008

In Parts 1 and 2, I attempted to figure out what a starting QB --- an actual regular starting QB, not a placeholder like say Chris Redman --- is worth to a team.

I came up with an empirical answer of 2.3 points per game, and I used a sort of thought experiment to convince myself that that is about right.

Ultimately, though, we don't really care about the points. We care about the wins. So I translated the points into wins (just about exactly one win per season, it turned out). But another way to go would be to skip the points step and go straight to the wins. That is, instead of looking at how many points per game a team lost when forced to play its backup, look directly at how many "wins per game" they lost.

When I do that with the same data set as the previous study, I get an average drop of .038 in winning percentage, which comes out to 0.6 wins per season. That's lower than the estimate based on points, which might indicate that, as some commenters speculated, the points go down due to a change to a more conservative game plan and/or possibly extra effort by the defense (though I checked, and defenses did not allow fewer points in games started by the backup.)

I then decided to make absolutely sure I wasn't biasing the results toward the backups by intentionally trying to bias them toward the starters. In particular, I threw out all the teams whose starting QBs had a below-.500 record. So I was looking at all teams since 1990 whose game one starting QB started at least eight games and whose passing stats were at least league average and whose record was at least .500. That sample includes 31 teams. Using those teams, the average difference in winning percentage between starter and backups was .108, which would imply 1.7 wins per year.

Make of that what you will.

Another interesting comment from the previous threads is that perhaps a backup quarterback will do better in his first game or two than he will in later games when opposing defenses presumably have a better idea what to expect from him.

To test this, I ran a regression. I took each game involving the teams in the original sample and recorded the following bits of data about it.

1. The overall season-long offensive quality of the team, as measured by offensive SRS.

2. The quality of the defense they faced, as measured by defensive SRS.

3. Whether the starting quarterback was the starter or a backup.

4. If a backup, whether it was his first week starting or not.

[I should have included home field here, but just forgot.]

For the output variable, I used points scored (for that game) above the league average for the year.

Results:

1. The coefficient on the starting QB variable was 2.4 (points per game), which matches up very well with our estimate from yesterday. That's reassuring.

2. The coefficient on the "first week starting" variable was -0.1 and was nowhere near being significant. So no evidence for a surprise effect.

Finally, I used a regression to get another estimate on the winning question.

Inputs:

1. offensive quality - defensive quality

2. starting QB or not

Output:

Win or loss

The best-fit formula is this:

Est. probability of winning =~ 1 / (1 + e^(.3083 - (pointdiff)*(.1649) - (starting QB?)*(.2842)))

So for example, if your offense was average and your opponent's defense was 5 points better than average (pointdiff = -5), and you had your starting QB (starting QB = 1), your probability of winning would be about 30%. Against the same defense without your starting QB, your chance would be about 24%.

If your offense was average and your defense was average, then your probability of winning drops by about seven percentage points depending on whether your starter is playing or not.

Six or seven percentage points times 16 games yields, again, almost exactly one win per season. More verification of the prior estimates.

11 Comments | Posted in General, Statgeekery

What’s a starting QB worth? Part II

Posted by Doug on August 19, 2008

Yesterday I asked you to speculate on how many points per game teams have historically lost when their starting quarterback was replaced by a backup.

Before I tell you the results, let's walk through a theoretical exercise....

If you take an average offensive team, let's say the 2008 Redskins, and you assume that they lost ALL their offensive starters for the season, how many points do you think they'd score per game in 2008?

They'd be rolling with the likes of Todd Collins, Ladell Betts, Devin Thomas, Malcolm Kelly, Fred Davis, and a backup offensive line. Arguably, you might give them the services of Antwaan Randle El instead of Kelly. They might go out and sign some veteran Shaun Alexander-type players off the street.

I'd say that offense scores about 12 points per game. They couldn't be that much worse than last year's Chiefs or 49ers, who averaged about 14 points per game. The last three expansion teams combined have averaged 16 points per game and all were above 13. Twelve points per game would be the second-lowest figure of the last seven seasons (thank you 2006 Raiders) and would have been last in the league in seven of the last ten years.

If you're willing to buy 12 points per game, then you've just agreed that an entire average offensive starting eleven is worth about 9 or 10 points per game.

Now, what percentage of an average offense does the quarterback account for? 20%? 30%? 40%?

If you say 30%, then the other ten are worth a combined 70%, or 7% each on average. That makes the QB worth more than four times as much as a typical non-QB offensive player. Is the QB worth more than the two guards, the center, and the right tackle combined? Is he worth more than the tight end, both wide receivers, and the running back combined? I don't think so.

I'm not sure how reliable the data accompanying these purty pictures are, but this link (and those that follow) give the average salaries by position as follows:

QB - 1.97 million
OL - 1.27 million
WR - 1.05 million
RB - .96 million
TE - .86 million

That would imply that 16% of the total salary paid to offensive players goes to quarterbacks. I believe that includes all players, not just starters, but I don't see why the starting-eleven ratio would be too much different.

In short, if NFL General Managers believed that quarterbacks were worth (more than) four times more than wide receivers, why do they only allocate twice the resources to quarterbacks? And if NFL GMs don't think quarterbacks are worth four times more than wide receivers, then why do you?

Anyway, if you don't agree, fill in your own number and go with it. My number would be around 20% or 25%, which would make the QB worth about two-and-a-half to three times what a typical non-QB offensive starter is worth.

So a typical QB accounts for about 20% to 25% of the offense, and a typical starting eleven is worth about 10 points per game. Thus, a typical starting quarterback is worth around two to two-and-a-half points per game.

The result of the study I described yesterday is the empirical verification of the theoretical observations above. Actual teams who have replaced their starter with a backup have on average dropped off by 2.3 points per game.

As I mentioned yesterday, I tried lots of different variations on the definition of a starting quarterback. These tweaks made the sample sizes grow or shrink, and they made the "average starting quarterback" better or worse. But in virtually every case, the number was between 2 and 3.

How does that translate to wins?

A regression of Simple Rating System rating to wins says that adding one point per game will add about .45 wins over the course of a season. So a typical starting quarterback is worth 2.3 points per game, and 2.3 points per game is worth just about one win per season. (A Pythagorean calculation, by the way, would give a very similar result.)

If this still seems too low, let me rattle off some examples:

In 2007, the Texans scored more points with Sage Rosenfels starting than with Matt Schaub starting.

In 2006, the Eagles scored more points with backup Jeff Garcia than with Donovan McNabb.

In 2005, the Jags were better with backup David Garrard than with starter Byron Leftwich.

If you're tempted to raise an objection on the grounds that David Garrard is too good a backup to be considered typical, I will overrule it. Part of the point of this is that sometimes, backups are better than you think they are. David Garrard was the very definition of a backup quarterback when he replaced Byron Leftwich in 2005. And Leftwich, who had an 8-3 record as a starter and a 15/5 TD/INT ratio, certainly looked like an above average starting quarterback.

The 2001 Vikings scored more points (per game) with Spergon Wynn and Todd Bouman than with Daunte Culpepper.

The 2000 Saints' offense was much more productive with a young backup named Aaron Brooks than it was with veteran starter Jeff Blake, who had been having a fine season.

The 1998 Broncos scored more with Bubby Brister playing than with John Elway.

The 1996 Dolphins scored more with Craig Erickson than with Dan Marino.

And the list goes on.

There are, of course, lots of examples of the opposite thing happening. But when you add them all up, it comes out to an average of 2.3 points per game.

In closing, I'll mention that you could run through the same exercise for a particular QB that we just did with an average QB. It'll still just be conjecture, but it'll be fun. Take Tom Brady for instance.

If the Patriots lost their entire starting eleven tomorrow, how many points would they score? I'm inclined to say maybe 16 per game, because Belichick is a genius and the Patriots do everything The Right Way and John Lynch would probably move to tight end and all that sort of thing. With their actual starting eleven, I'd go ahead and give them credit for the 36 points per game they scored last year. On one hand, they probably caught a bit of lightning in a bottle last season and can't keep up that pace. But on the other hand, they weren't playing with their actual starting eleven all season either. If they had all eleven guys for 16 games this season, they probably could match last season's output. So I'll estimate that the Patriots' starting offense is worth 20 points.

Brady is probably a bigger part of the Patriots' offense than a typical quarterback is to a typical offense, so maybe give him credit for a third of that. Then round up, and you're at 7 points per game. That's right around three wins. I believe Vegas is currently showing an over/under of 12 or 12.5 wins for New England, so the above says that the Patriots would be a 9- or 10-win team if they lost Brady tomorrow.

[EDIT: it just occurred to me that the Vegas lines have some probability of a Brady injury already built into them. If New England were assured of Brady's services for 16 games, the over/under would probably be 13 wins. Maybe 13.5, though I don't think it would go that high. So I think that means that my estimate is that New England would be a solid 10-win team (maybe 11) without Brady.]

Does that sound about right?

29 Comments | Posted in General

What’s a starting QB worth?

Posted by Doug on August 18, 2008

If Ben Roethlisberger or Drew Brees or David Garrard or Eli Manning or Jake Delhomme were to go down with an injury and be lost for the season, how much would it cost his team in the W column by the end of the year?

Here's a quick study, made possible by the new QB start data.

The outline is this: take all teams who lost their starting QB for some games during the season, look at the team's points per game with the starting QB compared to its points per game with the backup QB, and then average the differences. This will give a rough estimate of how many marginal points per game a typical starting QB adds compared to a typical backup QB.

Seems pretty straightforward. But as you might imagine, there are a lot of details to consider.

Mainly, what is "a starting QB" anyway? For the 2007 Atlanta Falcons, which QB --- Harrington or Redman --- goes in the starter column, and which goes in the backup column? The answer is neither of the above. For the purposes of this study, I want to throw out teams like the 07 Falcons altogether, and consider only teams that had a clear starter who was performing reasonably well, and were forced to replace him with his backup because of injury.

Because I don't have historical injury info, I have to make some generalizations. So here are the teams I dug out of the database. I found all teams since 1990 satisfying the following:

1. the team's week one starter started at least 8 games and was above the league average in terms of adjusted net passing yards per attempt.

2. the team had other QBs who started at least three games during the season, not counting the potentially garbage-time-infested 16th game.

This query isn't perfect. I'm sure it will include a few teams I don't want to include and exclude a few teams I don't want to exclude, but I think it mostly hits the mark. In 2007, it gives us the Texans and Jaguars. Those are both teams we'd want to include. We also might have wanted to include the Rams, but the query doesn't pick it up because Marc Bulger's numbers were below average. If we relax the above average condition, we'll end up pulling in teams like the Raiders and Falcons, and I don't want to do that. If I'm asking how much a starting quarterback is worth, Josh McCown and Joey Harrington are not the starting quarterbacks I'm talking about.

In 2006, it gives us:

the Panthers, who were forced to replace Delhomme with Weinke for a few games.

the Redskins, who replaced Mark Brunell with Jason Campbell. It's questionable whether this should be included or not, as the Redskins were not winning when they made the switch, though Brunell's numbers were much more respectable than I remember them being.

the Eagles, who had a memorable several games with Jeff Garcia replacing Donovan McNabb. You might argue that Garcia is better than a typical backup, but that would be 100% revisionist. At the time, nobody thought the Eagles had a chance when McNabb went down. Nobody.

The point is, it's tough crafting a query that will pick up exactly the teams you want. The alternative is to go through the list by hand and decide which teams to include. This will severely limit the sample size (I don't remember exactly why Steve Pelleur replaced Steve Deberg in 1989) and will also introduce a lot of subjectivity into the process.

My solution is to use a rote query, but then try lots of different sets of parameters and see if they change the results. I tried using 110% of league average; I tried using 90% of league average; I tried requiring that the starter had a .500-or-better record in addition to above-average passing numbers; I tried requiring only seven games (instead of eight) for the starter and I tried requiring only 2+ games (instead of 3+) for the backup; I varied the minimum year. The results were surprisingly robust. The conclusions wouldn't change at all.

OK, take a guess. What's the number? How many points per game better is a team with its starting QB (as defined above) compared to its backup QB?

I'll post the answer tomorrow.

17 Comments | Posted in General

They’re called the what, Part 2

Posted by Chase Stuart on August 14, 2008

On Tuesday, I looked at how the AFC franchises got their nicknames. The comments provided great information on some things I missed, and hopefully the local fans can provide inside info again today. Let's take a look at the NFC.

Dallas Cowboys: The Cowboys entered the NFL in 1960 while the Oilers entered the AFL, giving Texas a pair of professional football teams. An earlier franchise had been called the Dallas Texans, but it folded after a year. Dallas nicknames in professional sports haven't been very original -- you've got the Rangers, Stars, Mavericks, and Cowboys. But before settling on 'Cowboys', the NFL franchise first picked Steers and then Rangers as the team nickname. Somehow I don't think the Dallas Steers cheerleaders would have been very popular.

New York Giants: New York, like Pittsburgh, took the same team name that the popular baseball team used. While the New York baseball Giants went to San Francisco, the New York football Giants remained in New York. So how did the baseball team get their name? For two seasons, they operated as the New York Gothams. According to the San Francisco Giants website, the change to Giants occurred midway through the 1885 season. "On June 3, after a rousing extra-innings victory over Philadelphia, manager Jim Mutrie was so overcome with emotion that he supposedly blurted out a description of his team that immediately became the franchise's new nickname. He called them his Giants."

9 Comments | Posted in General

They’re called the what?

Posted by Chase Stuart on August 12, 2008

Since the 2008 season is almost here, I decided it would be good to teach my girlfriend about which teams are in which divisions, along with some NFL history. While I'm sure she got way more than she bargained for, she also asked me some questions that I really couldn't answer. For one, she said, are there lots of Cardinals in Arizona? Showing off my knowledge, I was able to say "of course not, honey; the Cardinals actually started off in Chicago." To which she replied "I don't think there are many cardinals in Chicago, either." Needless to say, I had no response to that. So we went to Wikipedia and this neat link from the Pro Football Hall of Fame. I was surprised to read how many of the teams got their nicknames, and I thought some of the faithful PFR blog readers might be curious to hear about it, too.

Buffalo Bills: Buffalo had an NFL franchise as early as 1922, the Buffalo All-Americans. Two years later they were renamed the Buffalo Bisons, until the team folded during the Depression. When the AAFC was created, Buffalo was given a franchise, and in 1946 the AAFC's Buffalo Bisons were born. The next year the team changed the nickname to 'Bills', and played until the league folded in 1949. There are two different stories to explain the change. According to Wikipedia, the team was given the name Bills after the (at the time) famous barbershop quartet that was formed in Buffalo. Yes, it may be that the original Buffalo Bills were named after an a capella group. According to the NFL, a fan contest was held to rename the team, and the winning entry was 'Bills', after he famous western frontiersman, Buffalo Bill Cody.

Whatever the origin, when Ralph Wilson was given an AFL team in Buffalo, he decided to take the old name from the AAFC franchise.

Miami Dolphins: Miami was one of the two AFL expansion franchises (Cincinnati was the other), and the first major professional sports team in the state. The AAFC did have the Miami Seahawks for a year, but a fan contest chose the name 'Dolphins' for the AFL club. Other finalists included the: Mariners, Marauders, Mustangs, Missiles, Moons, Sharks, and Suns. As you'll continue to see, sports fans and NFL franchises seem to love alliteration. According to the Pro Football Hall of Fame, owner Joe Robbie said he liked the name because "the dolphin is one of the fastest and smartest creatures in the sea."

22 Comments | Posted in General

Award winners now listed at p-f-r

Posted by Doug on August 8, 2008

If you go to a year page, like say 1973, you will now see a list of award winners for that year:

AP MVP                                  O.J. Simpson
Newspaper Ent. Assoc. MVP               O.J. Simpson
Bert Bell Award (Player of the Year)    O.J. Simpson
AP Offensive Player of the Year         O.J. Simpson
AP Defensive Player of the Year         Dick Anderson
Super Bowl MVP                          Larry Csonka
AP Offensive Rookie of the Year         Chuck Foreman
AP Defensive Rookie of the Year         Wally Chambers
Walter Payton Man of the Year           Len Dawson
AP Comeback Player of the Year          Roman Gabriel

And if you go to a player page, you'll see his awards listed in the leaderboard box. Here's Barry Sanders:

1989 NFL AP Offensive Rookie of the Year
1991 NFL Bert Bell Award (Player of the Year)
1994 NFL AP Offensive Player of the Year
1997 NFL AP MVP
1997 NFL PFWA MVP
1997 NFL Newspaper Ent. Assoc. MVP
1997 NFL Bert Bell Award (Player of the Year)
1997 NFL AP Offensive Player of the Year

Here is a master list of awards. We lack Coach of the Year. Aside from that, are there any other awards we should add?

6 Comments | Posted in General, History, P-F-R News

New players and Super Bowl Champions

Posted by Chase Stuart on August 7, 2008

In case you haven't heard, the Jets traded for Brett Favre last night. While New York went just 4-12 last season, the Jets had arguably the most impressive off-season of any team in the NFL... and that was before adding Brett Favre. To recap, the Jets added Kris Jenkins at NT, Calvin Pace at OLB, and Vernon Gholston at OLB. On offense, New York signed G Alan Faneca, T Damien Woody and FB Tony Richardson, and drafted TE Dustin Keller. The Jets threw a ton of money at the big holes on the team -- blocking, run stopping, and attacking the passer. Keller, who is in the mold of Dallas Clark and is more wide receiver than tight end, was supposed to be the big play threat the Jets needed. But after all these moves, the Jets biggest hole was still the one spot you can't hide.

Until now. The addition of Favre instantly makes the Jets a legitimate playoff threat, and who knows what else. There are lots of things to talk about today, but here's the first thing that came to mind: how often are teams led to the Super Bowl by new players? As it turns out, not that frequently. Here's a look at five of the biggest moves:

  • Marshal Faulk and Kurt Warner, 1999. Easily the two biggest acquisitions that any Super Bowl team has made, and it came in the same year. Faulk was picked up for a song in a trade with Indianapolis, and Kurt Warner came in just a few hops away from bagging groceries. We all know what happened here.
  • Tony Dorsett, 1977. The Pitt Panther star became an instant hit in Dallas, ranking second in the league in rushing touchdowns and averaging 4.8 YPC. Dorsett chipped in four TDs in three post-season games, helping the 'Boys get over the hump and win Super Bowl XII.
  • Ronnie Lott, 1981. Like Dorsett four years earlier, Lott was an instant hit in the pros, and that was before he helped redefine the safety position. As a rookie he led the league in return touchdowns, and was named an All Pro at cornerback. In the playoffs, his fourth quarter interception iced the 'Niners first playoff victory.
  • Deion Sanders, 1994. After being named All Pro his last two seasons in Atlanta, Sanders was named to his third straight All Pro (and Pro Bowl) team in San Francisco. His 303 yards on interception returns still ranks as the third most in NFL history. Sanders won the Defensive Player of the Year award, and helped the 49ers end the Cowboys run as champions. The following year, Sanders went to Dallas, and won another Super Bowl.
  • Sam Adams, 2000. Sure, Ray Lewis and Rod Woodson were the big names on that Ravens defense, but Sam Adams was the only other Pro Bowler for Baltimore that year. Adams' huge body in the middle was a big reason why Lewis was able to be so dominant that season, and why the Ravens were able to win the Super Bowl with Trent Dilfer at quarterback.

What about QBs? Only three Super Bowl QBs were in their first year with their team -- Trent Dilfer (2000), Kurt Warner (1999) and Earl Morrall (1972). In addition, Jim Plunkett (1980) and Roger Staubach (1971) both played just sparingly with their teams before guiding them to the Super Bowl in those years.

As for Favre's age (he's 38 now, and turns 39 in October), does history say Favre has a chance? The 38 year old Favre was terrific, so that's probably the best sign that the 39 year old Favre will be very good. Warren Moon, John Elway, Phil Simms, Joe Montana, Craig Morton, Doug Flutie and Earl Morrall all had at least one very good year at 38 or older.

13 Comments | Posted in General

QB start data

Posted by Doug on August 6, 2008

Thanks to some serious research by a blog reader named Scott K, we now have data on which quarterbacks started which games all the way back to 1960.

Even though I'm opposed to the oversimplification of crediting wins and losses to quarterbacks, QB win-loss records are by far the most frequent request I get. So I've added them to the player pages, the team pages, and various other pages.

There's also no limit to the amount of database hot dogging I can do with this info in the database. For example...

19 Comments | Posted in General

What great running back was most helped by his offensive line? Part II

Posted by Doug on August 5, 2008

In yesterday's post I used a variety of metrics to determine which running back was most helped by his offensive line. All of them were lacking in one way or another, so I am going to make a more sophisticated effort with this post. Will it be a more accurate effort? I'll let you decide.

First I used my Approximate Value method to construct an aging curve for offensive linemen. This topic is itself enough for a whole post or more, but for now I'll skip it and just show you the curve.

Age  PctOfPeak
============
21 => 0.48
22 => 0.48
23 => 0.57
24 => 0.81
25 => 0.93
26 => 0.97
27 => 1.00
28 => 1.00
29 => 0.97
30 => 0.91
31 => 0.90
32 => 0.88
33 => 0.78
34 => 0.76
35 => 0.77
36 => 0.63
37 => 0.62
38 => 0.62
39 => 0.62
40 => 0.62

These numbers are fractions of peak AV. So according to this, a typical lineman has a pretty flat peak from age 26 to 29. He loses about 10% of that value by his age 30 season, and another 10ish percent by age 33. By age 40, if he's still around, he's about 60% of the player he was at his peak.

Next, I take every offensive lineman and define his Peak AV as the average of his three (not necessarily consecutive) best seasons.

Then, for each season, I multiply his peak AV by the appropriate age multiplier and assume that's about how good he was in that year.

The idea here is to get an estimate for how good a lineman was in each year of his career without making it so directly tied to the quality of his team and the honors and awards that he happened to win in just that year.

Alright, so now we've got a quality estimate for every lineman for every year. And, for all its potential faults, I do think it successfully addresses some of the concerns of the metrics we used yesterday: Anthony Munoz is distinguished from Frank Winters; non-pro-bowlers are not counted as useless; a decrepit old Bruce Matthews is not counted as equal to a prime Bruce Matthews.

Below is the same list of 100 running backs from yesterday, this time sorted by the (carry-weighted) average estimated (as above) quality of all five starting offensive linemen on each team they played for:

Jim Brown            54.99
Calvin Hill          51.96
Jim Taylor           49.74
Mark van Eeghen      49.19
Chuck Foreman        48.32
Mike Garrett         47.52
Lenny Moore          47.13
Roger Craig          46.76
Larry Csonka         45.83

16 Comments | Posted in Approximate Value, General

What great running back was most helped by his offensive line? Part I

Posted by Doug on August 4, 2008

Following is a list of the top 100 rushers in the NFL/AFL since 1950, sorted by the average number of pro bowl offensive line teammates per season.

Jim Brown             2.26
Eric Dickerson        2.12
Clem Daniels          1.93
William Andrews       1.92
Robert Smith          1.88
Emmitt Smith          1.79
Jim Taylor            1.77
Priest Holmes         1.68
Bill Brown            1.65
Shaun Alexander       1.62
Lawrence McCutcheon   1.61

8 Comments | Posted in General, P-F-R News

AV tentatively extended back to 1950

Posted by Doug on August 1, 2008

The AV formula for the seasons in the 1950--1969 range is quite a bit different from the post-merger formula. It's quite a bit simpler, in fact, so this should really be considered Approximate Approximate Value.

Nonetheless, I think it's interesting enough to publish, with the understanding that it's still very much in flux and, of course, even when it's no longer in flux it'll still fail to be everything we'd like it to be.

For those of you who have been following the AV discussion since the beginning, I apologize in advance for the recap, but I want to make sure this is in context for people stumbling upon this page blind. With that in mind, I'll dig up a few quotes on the purpose of the AV system. This page has more details and links to further discussion.

The Approximate Value (AV) method is my attempt to put a single number on a player-season by a player at any position from any year

...

AV is not meant to be a be-all end-all metric. Football stat lines just do not come close to capturing all the contributions of a player the way they do in baseball and basketball. If one player is a 16 and another is a 14, we can’t be very confident that the 16AV player actually had a better season than the 14AV player. But I am pretty confident that the collection of all players with 16AV played better, as an entire group, than the collection of all players with 14AV.

Essentially, AV is a substitute for — and a significant improvement upon, in my opinion — metrics like “number of seasons as a starter” or “number of times making the pro bowl” or the like. You should think of it as being essentially like those two metrics, but with interpolation in between. That is, “number of seasons as a starter” is a reasonable starting point if you’re trying to measure, say, how good a particular draft class is, or what kind of player you can expect to get with the #13 pick in the draft. But obviously some starters are better than others. Starters on good teams are, as a group, better than starters on bad teams. Starting WRs who had lots of receiving yards are, as a group, better than starting WRs who did not have many receiving yards. Starters who made the pro bowl are, as a group, better than starters who didn’t, and so on. And non-starters aren’t worthless, so they get some points too.

With that, here is AV's guess at the greatest players in 1950--present NFL/AFL history:

Reggie White           163
Jerry Rice             159
Alan Page              157

Aside: one of the side benefits of undertaking projects like this is that, even if you don't agree with what your metric ultimately says --- and I suspect few people will agree with Alan Page as the third-greatest player in post-1950 NFL history --- you end up learning a lot. I learned, for example, just how insanely great the Purple People Eaters were.

In 1969, the Viking were 50 points better than the second-best defensive team in terms of points allowed. In 1970, the difference between the first-place Vikings and the second-place Lions was nearly as big as the gap between the Lions and average. They were a top-3 defense in seven of the eight seasons from 1969 to 1976, including two 1985-Bears-esque seasons.

AV recognizes Alan Page as the greatest member of the one of the greatest units of all time, which accounts for his higher-than-expected showing on this list. Carl Eller and Paul Krause will also appear soon.

The early-70s Vikings were like a substantially better version of the late-90s / early-00s Buccaneers. As you'll see shortly, AV interprets Derrick Brooks as the poor man's Alan Page and ranks him higher than most people think he should be ranked.

Brett Favre            147
Bruce Smith            146
Dan Marino             146
Rod Woodson            141
Johnny Unitas          141
Carl Eller             140
Lawrence Taylor        139
Merlin Olsen           139
Fran Tarkenton         138
John Elway             138
Anthony Munoz          137
Peyton Manning         136
Steve Young            134
Derrick Brooks         134
Andy Robustelli        133
Chuck Bednarik         133+

Bednarik has a '+' to indicate that his career started before 1950, so his total AV is greater than the number listed.

More names after the jump...

24 Comments | Posted in Approximate Value, General