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Similarity Scores for New 2007 Quarterbacks

Posted by Jason Lisk on January 29, 2008

Several new quarterbacks started for the first time in 2007. Derek Anderson, Kellen Clemens, Brodie Croyle, Tarvaris Jackson, Sage Rosenfels and Matt Schaub, along with rookie Trent Edwards, all threw 150 passes for the first time in their careers. Jay Cutler and Vince Young got experience their rookie seasons, and were the full-time starters in year two; Jason Campbell and David Garrard had some previous playing experience but also became full-time starters in 2007.

I am going to examine the new 2007 quarterbacks to see what history says about their futures. Right before the 2007 season, I wrote "In Search of the Next Brady or Bulger", which took a look at quarterbacks who were drafted outside the top 50 selections in the draft. One of the interesting things for me was that all of the late round successes showed signs of being successful right away--which may be contrary to some conventional wisdom about quarterback development. All were close to average (if not better) in their first real opportunity to start, and most were above average by their second season. But those were only the later round quarterbacks. Here, we will take a look at all the quarterbacks who have played since 1978, to find the most comparable seasons for each of these new quarterbacks.

Here is the method I used to find the most similar seasons for each player:

1. Start with 1000 points;
2. Subtract 1 point for every 1 pass attempt difference;
3. Subtract 20 points for every 1.0% difference in completion percentage;
4. Subtract 20 points for every 0.1 difference in yards per attempt;
5. Subtract 100 points for every 1.0% difference in touchdown percentage;
6. Subtract 100 points for every 1.0% difference in interception percentage;

I excluded all true rookie seasons (except for the case of Trent Edwards, in which case I only included them). I then made age adjustments by subtracting 100 points if the subject player and comparable season were one year apart, and an additional 50 points for each additional year difference in age.

The result is a list for each player of previous quarterbacks who are similar when considering various statistical measures of quarterback performance--completion percentage, yards per attempt, touchdown percentage, and interception percentage.

I'll note that just because a player is "similar" doesn't mean they are the same. Our subject quarterback may have put up better numbers in all categories, or worse numbers in all categories, or identical numbers in some categories and disparate ones in others. This is why Tom Brady and David Carr can appear next to each other on a similarity list. I would view the list more in terms of a range of possibilities for that player, with the more similar players weighted more heavily. As you will see, some players have lots of similar historical quarterbacks, while some, such as Rosenfels and Schaub, who were a little older, productive, but with relatively few passes thrown, have fewer comparables.

The similarity lists hint at which underlying performance stats are most important for predicting future performance. If you were to guess before seeing the lists, what do you think is most important? One of the categories has, from what I am seeing, almost no predictive value, once you know how the player performed in the other categories.

That category is interception %. A young quarterback with an above average interception % who performs reasonably well in other areas is not necessarily a bad thing for the future. Above average performances in touchdown %, completion % or yards per attempt seem to be positive indicators; a poor performance in these categories is not a good sign.

Perhaps it is the Tom Brady/Peyton Manning effect, where a mere 30 touchdown passes, or 7.5 yards per attempt, are seen as average, but there are several promising new quarterbacks. You might be surprised to find that one of the quarterbacks on this list has three present or future hall of famers at the top of his similarity list, in the first seasons in which each won a Super Bowl. I'll avoid comment on some others ("if you can't say anything nice . . . .) At the end, I even invent a player by combining two of the quarterbacks on this list, and in the process, may have found a 2008 sleeper quarterback.

The list is presented in alphabetical order (the + sign indicates a season that was the first for that similar player's career throwing 150+ pass attempts in a non-rookie season):

DEREK ANDERSON [AGE 24, 527 ATT, 56.5% COMP, 7.2 YPA, 5.5% TD, 3.6% INT]

   player             year     age    sim score
================================================
1  Dan Marino	      1985	24	852
2  Drew Bledsoe	      1997	25	718
3  Randall Cunningham 1987	24	701+
4  Aaron Brooks       2001	25	674
5  Jim Everett        1988	25	672
6  John Elway	      1984	24	668+
7  Michael Vick	      2004	24	661
8  Jim Zorn  	      1979	26	657
9  Don Majkowski      1989	25	650
10 Eli Manning	      2005	24	635+
11 Jeff Blake	      1995	25	634
12 Timm Rosenbach     1990	24	632+
13 Jake Plummer	      1998	24	609+
14 Chris Miller	      1990	25	606
15 Peyton Manning     2000	24	603
================================================

JASON CAMPBELL [AGE 26, 417 ATT, 60.0% COMP, 6.5 YPA, 2.9% TD, 2.6% INT]

   player             year     age    sim score
================================================
1  David Carr	      2005	26	825
2  Josh McCown	      2004	25	735
3  Steve McNair	      1999	26	730
4  Bernie Kosar	      1989	26	728
5  Neil Lomax	      1986	27	725
6  Rich Gannon	      1991	26	719
7  Steve McNair	      1998	25	710
8  Chris Simms	      2005	25	703+
9  Neil Lomax	      1985	26	703
10 Todd Collins	      1997	26	701+
11 Byron Leftwich     2004	24	692+
12 Ken O'Brien	      1987	27	692
13 Joey Harrington    2004	26	688
14 Jim Kelly	      1987	27	684
15 Matt Hasselbeck    2001	26	684+
================================================

KELLEN CLEMENS [AGE 24, 250 ATT, 52.0% COMP, 6.1 YPA, 2.0% TD, 4.0% INT]

   player             year     age    sim score
================================================
1  Andrew Walter      2006	24	778+
2  David Woodley      1982	24	730
3  Randy Wright	      1987	26	726
4  Todd Blackledge    1984	23	723+
5  Don Majkowski      1988	24	717+
6  Browning Nagle     1992	24	711+
7  Steve Walsh	      1990	24	704+
8  Rick Mirer	      1996	26	700
9  J.P. Losman	      2005	24	681+
10 Steve Young	      1986	25	657+
11 Josh McCown	      2003	24	654+
12 David Klingler     1994	25	642
13 Kyle Boller	      2005	24	641
14 Craig Whelihan     1997	26	639+
15 Danny Kanell	      1997	24	626+
15 Ken Dorsey         2004	23	626+
15 Tim Hasselbeck     2003	25	626+
================================================

BRODIE CROYLE [AGE 24, 224 ATT, 56.7% COMP, 5.5 YPA, 2.7% TD, 2.7% INT]

   player             year     age    sim score
================================================
1  Koy Detmer	      1998	25	761+
2  David Klingler     1993	24	720+
3  Ken Dorsey         2004	23	713+
4  David Klingler     1994	25	710
5  Brooks Bollinger   2005	26	675+
6  Cade McNown	      2000	23	663+
7  Josh McCown	      2003	24	659+
8  Danny Kanell	      1997	24	629+
9  David Woodley      1982	24	619
10 J.P. Losman	      2005	24	612+
11 Tony Banks	      2000	27	611
12 Tim Hasselbeck     2003	25	607+
13 Chad Hutchinson    2004	27	597
14 Rick Mirer	      1994	24	595+
15 Don Majkowski      1988	24	589+
================================================

JAY CUTLER [AGE 24, 467 ATT, 63.6% COMP, 7.5 YPA, 4.3% TD, 3.0% INT]

   player             year     age    sim score
================================================
1  Tom Brady	      2001	24	803+
2  David Carr	      2004	25	746
3  Joe Montana	      1981	25	745
4  Troy Aikman	      1992	26	737
5  J.P. Losman	      2006	25	725
6  Daunte Culpepper   2001	24	713
7  Brett Favre	      1992	23	686+
8  Ben Roethlisberger 2006	24	683
9  Drew Brees	      2005	26	679
10 Philip Rivers      2006	25	678+
11 Peyton Manning     1999	23	674+
12 Jim Kelly	      1986	26	669+
13 Tony Eason	      1986	27	646
14 Peyton Manning     2000	24	641
15 Bernie Kosar	      1987	24	624
15 Peyton Manning     2001	25	624
================================================

TRENT EDWARDS [AGE 23, 269 ATT, 56.1% COMP, 6.1 YPA, 2.6% TD, 3.0% INT]

   player             year     age    sim score
================================================
1  Chris Miller	      1988	23	746
2  Matt Leinart	      2006	23	689
3  Rick Mirer	      1993	23	668
4  Vince Young	      2006	23	661
5  Bruce Gradkowski   2006	23	659
6  Kelly Stouffer     1988	24	651
7  Steve Walsh	      1989	23	650
8  Mike Pagel	      1982	22	631
9  Charlie Frye	      2005	24	630
10 Bernie Kosar	      1985	22	616
11 David Carr	      2002	23	613
12 Tim Couch	      1999	22	609
13 Cade McNown	      1999	22	584
14 Quincy Carter      2001	24	580
15 Kyle Orton	      2005	23	547
================================================

DAVID GARRARD [AGE 29, 325 ATT, 64.0% COMP, 7.7 YPA, 5.5% TD, 0.9% INT]

   player             year     age    sim score
================================================
1  Jake Plummer	      2003	29	655
2  Brian Griese	      2000	25	633
3  Chris Chandler     1994	29	615
4  Matt Hasselbeck    2005	30	615
5  Troy Aikman	      1995	29	611
6  Jim Harbaugh	      1995	32	609
7  Steve McNair	      2003	30	597
8  Steve Bartkowski   1983	31	587
9  Richard Todd	      1982	29	557
10 Wade Wilson	      1988	29	552
11 Brian Griese	      2004	29	547
12 Dave Krieg	      1986	28	543
13 Chad Pennington    2002	26	541+
14 Jeff Garcia	      2000	30	540
15 Joe Montana	      1985	29	536
================================================

TARVARIS JACKSON [AGE 24, 294 ATT, 58.2% COMP, 6.5 YPA, 3.1% TD, 4.1% INT]

   player             year     age    sim score
================================================
1  David Carr	      2003	24	867+
2  Kyle Boller	      2005	24	858
3  Drew Brees	      2003	24	798
4  Jim Everett        1987	24	792+
5  Troy Aikman	      1990	24	781+
6  Josh McCown	      2003      24	739+
7  Ken O'Brien	      1984	24	727+
8  Quincy Carter      2002	25	714+
9  Steve Walsh	      1990	24	709+
10 Dave M. Brown      1994	24	699+
11 Josh McCown	      2005	26	697
12 Brian Griese	      1999	24	691+
13 Don Majkowski      1988	24	690+
14 Steve Fuller       1980	23	688+
15 David Whitehurst   1979	24	675+
================================================

SAGE ROSENFELS [AGE 29, 240 ATT, 64.2% COMP, 7.0 YPA, 6.2% TD, 5.0% INT]

   player             year     age    sim score
================================================
1  Dave Krieg	      1987	29	665
2  Erik Kramer	      1994	30	632
3  Bernie Kosar       1992	29	615
4  Cody Carlson       1992	29	607+
5  Trent Dilfer	      2000	28	607
6  John Friesz	      1994	27	596
7  Pat Ryan	      1984	29	575+
8  Danny White        1982	30	561
9  Bubby Brister      1991	29	551
10 Marc Wilson	      1986	29	506
11 Vince Ferragamo    1983	29	505
12 Brad Johnson	      1996	28	489+
13 Gary Hogeboom      1987	29	485
14 Jim Kelly	      1989	29	485
15 Boomer Esiason     1990	29	484
================================================

MATT SCHAUB [AGE 26, 289 ATT, 66.4% COMP, 7.8 YPA, 3.1% TD, 3.1% INT]

   player             year     age    sim score
================================================
1  Troy Aikman	      1991	25	730
2  Joe Montana	      1982	26	617
3  Neil O'Donnell     1992	26	611
4  Marc Bulger	      2005	28	606
5  Brian Griese	      2002	27	602
6  Troy Aikman	      1994	28	601
7  Gus Frerotte	      1999	28	587
8  Mark Brunell	      1996	26	573
9  Jim McMahon        1985	26	553
10 Josh McCown	      2005	26	550
11 David Carr	      2004	25	541
12 Bernie Kosar	      1988	25	540
13 Tim Rattay	      2004	27	535+
14 Steve McNair	      2000	27	530
15 Elvis Grbac	      1995	25	515+
15 Matt Hasselbeck    2002	27	515
================================================

VINCE YOUNG [AGE 24, 382 ATT, 62.3% COMP, 6.7 YPA, 2.4% TD, 4.5% INT]

   player             year     age    sim score
================================================
1  Troy Aikman	      1990	24	794+
2  Charlie Frye	      2006	25	739+
3  Tim Couch	      2001	24	726
4  Chuck Long	      1987	24	697+
5  David Carr	      2003	24	692+
6  Dave M. Brown      1994	24	643+
7  Drew Brees	      2003	24	634
8  Brett Favre	      1993	24	632
9  Brian Griese	      1999	24	619+
10 Daunte Culpepper   2001	24	613
11 Carson Palmer      2004	25	602+
12 Jim Everett        1987	24	601+
13 Jake Plummer	      1998	24	584+
14 Byron Leftwich     2004	24	581+
15 Steve Fuller       1980	23	577+
================================================

MAGE ROSENSCHAUB [AGE 27, 529 ATT, 65.4% COMP, 7.4 YPA, 4.5% TD, 4.0% INT]

   player             year     age    sim score
================================================
1  Jeff George        1994	27	790
2  Marc Bulger	      2003	26	764
3  Dan Fouts          1979	28	732
4  Dan Marino	      1988	27	730
5  Joe Montana	      1983	27	711
6  Brian Griese	      2002	27	709
7  Peyton Manning     2001	25	706
8  Drew Bledsoe	      1999	27	701
9  Chad Pennington    2003	27	673
10 Drew Brees	      2005	26	671
11 Peyton Manning     2002	26	671
12 Stan Humphries     1992	27	669+
13 Jim Kelly	      1986	26	663+
14 Marc Bulger	      2004	27	661
15 Ken O'Brien	      1986	26	659
15 Steve Beuerlein    1993	28	659
================================================

This entry was posted on Tuesday, January 29th, 2008 at 7:15 am and is filed under General, History, Statgeekery. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.