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GQBOAT III: Career rankings (Weather, SOS and post-season included)

Posted by Chase Stuart on August 13, 2009

On Monday, I explained the methodology behind my system which ranks every quarterback-season in NFL history. On Tuesday, I presented the career leaders in the regular season and in the regular and post-season, combined. I also showed a list of the yearly leaders, in one and five-year increments. Yesterday, Doug did some outstanding and innovative work to provide (precise) strength of schedule and (approximate) weather adjustments for every quarterback-season since 1960. Today, we can add Doug's results to my formula to get a truer picture of the most productive quarterbacks in NFL history.

Implementing Doug's data is actually pretty simple. If before, QB A had 500 plays, averaged 8.0 converted yards per play, and the league average (excluding him) was 6.0 CY/A, then he would get credit for having 1000 converted yards of value added over average. Now suppose he had played half his games (and had half of his attempts) in domes, and the other half in what Doug calls "everything else." QB A would then have a weather adjustment of -0.20 CY/P (here, CY/P and ANY/A are similar enough to be interchangeable). Assuming further that he faced an easy schedule -- approximate 0.30 ANY/A easier than average -- then we could state that a perfectly average QB playing QB A's schedule and in QB A's environment would average 0.5 CY/P (or ANY/A) more than if our perfectly average QB faced an average schedule in an average environment. Therefore, we would downgrade QB A from 8.0 CY/P to 7.5 CY/P, and his total value would drop to 750 converted yards over average.

Using the same processes as before, here's the new career list. For players who retired before 1960, there is no weather (WX) or schedule (SOS) adjustment. For players who played partially in the '50s and partially in the '60s, their weather and schedule adjustments are based only on their games played after 1960.

Also, just like with the playoff data, the weather and schedule numbers don't "add up" (although it's not like you could add them up, anyway). I've listed career playoff, weather, and schedule data, but because I take a season-by-season approach to career rankings, someone could potentially be bad for their career in one of those categories but still grade out better once we implement those adjustments. It is, of course, rare for that to happen, but it would occur if in someone's best seasons they had great playoff/weather/SOS adjustments, and in their very worst seasons, they had even more significant playoff/weather/SOS adjustments going the other way. This isn't a flaw, but a good thing -- we care how QBs perform in the playoffs when they're in their prime and playing at their best, not when they're average (or worse) QBs at the beginnings or ends of their careers.

From left to right, the column headings are: attempts, value (over average), value rank, replacement (value over 3/4 of league average), replacement rank, post-season value (this is a raw career value, not the season-by-season sums), combined value (regular and post-season, season-by-season), combined value rank, weather adjustment (career value), strength of schedule adjustment (career value), final value (regular-season value, adjusted for weather and SOS, along with post-season value (not adjusted), in a season-by-season analysis) and final value rank. Whew.

ATT   VALUE   VRK  REPL   RRK  POST  CVAL   CRK    WX     SOS    FINAL   FRK  
5391   8451    4  13284    3   3397  11444    1    0.01   -0.07  11121    1   Joe Montana
5960  10492    1  16093    2    474  10934    2   -0.19    0.16  10722    2   Peyton Manning
8358  10410    2  16770    1     45  10787    3    0.01   -0.05  10434    3   Dan Marino
4149   8783    3  12735    6   1182   9950    4    0.03    0.00   9935    4   Steve Young
6467   8286    5  12838    5   -605   7862    6    0.06    0.15   8408    5   Fran Tarkenton
5604   7192    6  11828    7     97   7311    8   -0.01    0.19   8018    6   Dan Fouts
1744   6529    9   7844   27   1368   7949    5     -       -     7949    7   Sid Luckman
4475   6752    7  10337    9    667   7412    7    0.08    0.06   7800    8   Ken Anderson
9280   6157   11  13149    4   1017   7124   10    0.12   -0.02   7670    9   Brett Favre
5186   6696    8  11233    8    264   7175    9   -0.02    0.14   7599   10   Johnny Unitas
2995   6351   10   8432   17    590   6797   11     -       -     6797   11   Sammy Baugh
2958   5987   12   8548   15    848   6746   12   -0.02    0.03   6760   12   Roger Staubach
3741   5733   13   8711   14    909   6523   13    0.02   -0.02   6522   13   Len Dawson
3149   3948   28   6998   38   1949   5613   15    0.01    0.29   6126   14   Bart Starr
3653   4442   19   8468   16    873   5212   21    0.13    0.12   6072   15   Tom Brady
7250   4314   22  10256   10   1246   5409   19    0.01    0.05   5809   16   John Elway
2895   5517   15   8234   20   -115   5608   16     -       -     5608   17   Norm Van Brocklin
2626   5029   16   6600   42    776   5595   17     -       -     5595   18   Otto Graham
4715   3439   39   7774   28   1830   5303   20    0.01    0.00   5337   19   Troy Aikman
4491   3821   31   7735   29    -34   3809   33   -0.04    0.50   5202   20   John Brodie
2601   4363   20   6839   40    657   5031   22   -0.01   -0.02   4918   21   Daryle Lamonica
4262   5524   14   9632   11   -112   5447   18    0.02   -0.31   4814   22   Sonny Jurgensen
3557   4479   18   8300   18   1535   5915   14   -0.07   -0.26   4765   23   Kurt Warner
5205   4242   23   8777   13   -204   3976   27    0.14    0.01   4678   24   Boomer Esiason
4498   3755   33   7474   34    -13   3743   34    0.00    0.16   4361   25   Roman Gabriel
3740   3962   27   7960   25    -96   3950   28   -0.01    0.09   4157   26   Trent Green
3901   2885   45   6090   47   1617   4310   23    0.01   -0.06   4141   27   Terry Bradshaw
5076   3965   26   7393   36    -22   3948   30   -0.02    0.06   4000   28   Jim Hart
3676   4328   21   8214   21    -84   4241   24    0.01   -0.09   3975   29   Jeff Garcia
3762   4023   24   7258   37    102   4138   25    0.02   -0.10   3970   30   Joe Namath
4303   3451   37   7961   24   -303   3327   41    0.12    0.02   3807   31   Donovan McNabb
4687   3975   25   7553   33     -5   3911   31   -0.01    0.00   3764   32   John Hadl
 818   3440   38   4056   93    285   3691   35     -       -     3691   33   Cecil Isbell
3650   3872   29   7913   26    114   3978   26   -0.10    0.01   3634   34   Drew Brees
2551   3818   32   6191   45     10   3825   32    0.02   -0.10   3632   35   Bert Jones
2833   2891   44   5383   59    865   3565   39    0.09   -0.36   3551   36   Charlie Conerly
4544   3717   34   8095   23   -109   3685   36    0.01   -0.12   3397   37   Steve McNair
6701   2695   48   7416   35     98   2729   48    0.04    0.12   3349   38   Vinny Testaverde
2613   2389   57   5039   67    573   2973   45    0.06    0.09   3347   39   Mark Rypien
3793   2624   55   5441   57   1118   3674   37   -0.07   -0.14   3336   40   Ken Stabler
6823   3848   30   9584   12     61   3949   29   -0.19    0.06   3296   41   Warren Moon
3429   3384   40   6008   48    273   3636   38   -0.01   -0.09   3281   42   Bob Griese
3602   2679   50   6144   46    376   3031   44    0.03    0.03   3097   43   Joe Theismann
1175   2995   42   3414   115   -71   3062   43     -       -     3062   44   Arnie Herber
3365   2365   58   5714   53    442   2800   47    0.11   -0.06   3033   45   Bernie Kosar
4289   2692   49   6858   39     25   2722   49    0.08    0.02   2930   46   Randall Cunningham
4395   4762   17   8299   19  -1640   3377   40   -0.02   -0.52   2873   47   Y.A. Tittle
4206   3506   36   7572   31   -384   3140   42   -0.06   -0.06   2871   48   Rich Gannon
3042   2806   47   6254   44   -115   2707   50   -0.18    0.17   2662   49   Daunte Culpepper
4923   2944   43   7696   30   -460   2498   53   -0.04    0.07   2656   50   Jim Everett
2165   1961   66   4557   79     60   2022   71    0.09    0.14   2498   51   Carson Palmer
2573   1821   76   4351   87    504   2410   56    0.02    0.01   2450   52   Jim McMahon
2300   1932   70   3907   99    -78   1865   76    0.01    0.24   2386   53   Greg Landry
2338   1484   88   4030   94    625   2082   64    0.05    0.07   2370   54   Jeff Hostetler
2419   2156   63   4759   74   -257   1976   72    0.06    0.30   2340   55   Milt Plum
4779   3621   35   8138   22  -1022   2913   46    0.04   -0.19   2296   56   Jim Kelly
4594   3018   41   7566   32   -450   2637   51    0.01   -0.11   2283   57   Mark Brunell
2395   2251   61   5033   68   -191   2060   65    0.05    0.07   2273   58   Chad Pennington
1424   2671   51   3959   97   -440   2233   58     -       -     2233   59   Tommy Thompson
1905   1416   93   3778   102   546   1907   75    0.06    0.13   2232   60   Ben Roethlisberger
2689   2643   53   5014   70   -253   2379   57    0.02   -0.14   2186   61   Earl Morrall
 808   2173   62   3048   124   -51   2130   60     -       -     2130   62   Johnny Lujack
1617   2061   65   3566   111    29   2096   63     -       -     2096   63   Bob Waterfield
3593   2669   52   5509   56   -312   2436   55    0.09   -0.24   2075   64   Steve Grogan
1428   1849   72   3655   105    76   1922   74    0.01    0.09   2071   65   Philip Rivers
1307   1959   67   3618   107    15   1974   73    0.02    0.06   2064   66   Tony Romo
2937   2640   54   5020   69   -219   2457   54   -0.01   -0.23   2035   67   Billy Kilmer
2507   1882   71   4508   80    192   2151   59    0.01   -0.10   2026   68   Doug Williams
4007   2131   64   4697   75   -623   2047   68   -0.07   -0.08   2022   69   George Blanda
2151   1666   81   3948   98    -35   1671   84    0.03    0.13   1995   70   Doug Flutie
3347   2330   59   5999   50    307   2634   52    0.00   -0.22   1985   71   Matt Hasselbeck
3439   1937   69   5224   63   -275   1662   85    0.09   -0.01   1984   72   Brian Sipe
4647   1754   77   6001   49    334   2059   66    0.04   -0.06   1983   73   Phil Simms
3700   2546   56   5798   51   -958   2049   67    0.00   -0.61   1961   74   Bobby Layne
3786   2814   46   5593   54   -939   2032   69    0.00   -0.02   1940   75   Craig Morton

  • While Manning has definitely benefited from an easy home environment, that's been equalized by a harder than average schedule (that often includes New England and Pittsburgh).
  • Dan Fouts had a very difficult schedule most of his career. He faced great defenses in his division, and had the most difficult schedule of any top-ten QB. Ken Anderson -- the guy every stat nerd thinks should be in the Hall of Fame -- also faced a harder than average schedule and, of course, didn't play in the friendliest of climates. His resume keeps looking better.
  • Tom Brady moves up a bunch (in converted yards, if not rank) once we include weather, schedule and post-season adjustments. This jives with everyone finding him underrated by conventional statistics.
  • Sonny Jurgensen padded his numbers against the weak NFL East at the same time that John Brodie was facing the brutal NFL West. Look at how drastically the schedule adjustments change their career ranks. Jurgensen moves from #18 in combined value to #22 in final value; Brodie jumps from #33 to #20 in those categories. Does this mean history has overrated Jurgensen and underrated Brodie? Is it Brodie and not Jurgensen that deserves to be in the HOF?
  • Unsurprisingly, Kurt Warner takes a big hit once we include weather and schedule. We saw yesterday that his replacement, Marc Bulger, had the most favorable weather/schedule combo of all-time. He drops from #88 to #172 with those adjustments. And if we get around to strength-of-supporting cast analysis, ala the running backs post, Bulger (and Warner) would surely look even worse.
  • My system is no fan of Jim Kelly. As the 35th best QB of all-time in Value rank, he's probably ranked lower than he would by most lists. Then he drops to #46 when you include his terrible post-season performances in the biggest games. He drops to #56 once you include the weather and schedule adjustments, as he played most of his career in a very weak division defensively. It may be counterintuitive, but Kelly grades out as the worst modern era QB in Canton.
  • Frequent P-F-R commenter Brad O. writes that Donovan McNabb has a decent HOF argument to make. The schedule and weather adjustment only make McNabb look better, but he's still borderline in my analysis (and without a ring, even less borderline in most people's eyes). He's the anti-Bulger in that regard, as he's been saddled with below-average receivers for most of his career.
  • For what it's worth, I think having 4,000 converted yards over average is a good HOF litmus test. Seventeen of the 25 modern QBs to enter the Hall reached that mark, with Joe Namath only a hair behind. Of the others, two were not pure QBs (Blanda/Layne), Kelly and Moon racked up great raw numbers, Layne and Tittle had great reputations, and Griese had the rings. Going the other way, 11 QBs are at +4,000 and not in the Hall. Three -- Manning, Brady, Favre -- are locks. Then you've got Ken Anderson and Kurt Warner, two guys with clear HOF resumes. Then Brodie (undervalued due to schedule), Lamonica (short career), Esiason, Gabriel, Green and Hart. Esiason and Gabriel have been discussed, and most feel that they're "Hall of Very Good" types. Trent Green never got any respect, and I'm not sure why. Jim Hart? He has a good resume, and was very good for very long. Unfortunately, he had no playoff success of which to speak.

This entry was posted on Thursday, August 13th, 2009 at 7:29 am and is filed under Best/Worst Ever. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.