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

The History of the Black QB: Part II

Posted by Chase Stuart on February 8, 2008

If you've got a few minutes to spare, check out Part I of this series, although it's unrelated to today's post. Thanks to JWL, who pointed out the absence of J.J. Jones in that post, which has since been updated. If you notice any other absences from that list, please post their names in the comments. (I'm not considering players like Antwaan Randle El or Brad Smith as QBs, since they are really WRs who just run some trick plays.)

Pro-Football-Reference introduced sacks and sack yards lost as part of the new database. You can check out which QB has been sacked the most number of times in a single season or career. To date, this blog hasn't used the sack data too often, so I'm going to make an effort to incorporate this new and valuable information a bit more frequently into my posts.

How should we use sacks data when ranking QBs? Well, an incompletion is better than a sack, right? Therefore, a sack should count against completion percentage -- it was a pass attempt that failed. Further, the yards must be taken away from a QB's gross passing yards. So a QB that is 30 for 40, for 300 yards, with 5 sacks for 50 yards would have his stats translated to 30 for 45 for 250 yards. Does that seem right or fair to you? I feel pretty comfortable with taking all sacks and counting them as 1) incompletions and 2) negative yards.

We can use the sack data to calculate net yards per attempt. It's computed by taking an individual QB's passing yards, subtracting his sack yards lost, and dividing by [pass attempts + sacks]. This ratio is already calculated for you at every QB's PFR page. Kurt Warner in 2000 has the highest net yards per attempt in a single season, with a 9.0 average (and averaged 9.9 passing yards per attempt without factoring in sacks).

Why all this buildup? Because I'm going to rank the best QB seasons by a black QB, and this gives me a good excuse to use our new data. Further, we need to incorporate the rushing yards in here somehow. Reader "Boogie Down Enigma" made an interesting observation in a comment to a blog post about Mike Vick, when he compared him to Tom Brady. Please note that this was before the 2007 season, when Brady actually had great statistics for the first time in his career.

When Vick ran, he was essentially throwing screen passes to himself. When you consider that, you see he was essentially catching 7.9 screen passes per game for 57.6 yards per game.

The average game saw Brady complete 20 passes on 32.3 attempts for 227 yards, 1.5 touchdowns and 0.8 interceptions.

The average game saw Mike Vick complete 13.9 passes on 25.8 passes for 171.7 yards, 1.1 touchdowns, and 0.8 interceptions.

The average game saw Tom Brady run 2.5 times for 4.58 yards.

The average game saw Mike Vick run 7.9 times for 57.6 yards.

When you combine their rushing totals and treat the rushing attempts as completions and attempts because that is essentially what they were (Vick completing screen passes to himself), you see that it is appropriate to perhaps consider Vick as a regular season equal to Brady in terms of offensive production from the QB position.

Combining the rushing totals, you get this:

In the average game for Brady, 22 completions on 35 attempts for a 65% completion percentage for 232 yards, 1.6 TDs, and 1.1 turnovers, 6.7 yards per attempt.

In the average game for Vick, 22 completions on 34 attempts, 65% completion percentage, 229 yards, 1.4 TDs, and 1.3 turnovers, 6.8 yards per attempt.

That's some pretty interesting analysis that coincidentally matches up the two QBs almost perfectly. I like it the idea, and think that's a good way to think about Vick. . . but I don't think that's a good way to think about all QBs. Over half of all Peyton Manning's rushing attempts this season were kneel downs. So I don't really want to penalize QBs for essentially a negative one yard pass every time their coach decides the QB should sit on the ball. I don't know if anyone has ever done a study to meaningfully compare a QB's rushing yards to his passing yards. That is, which is better: A QB that passes for 3,000 yards and runs for zero yards or one who throws for 2,000 and runs for 1,000? Are they the same?

Here's an idea I've got, which I've pretty much plucked out of nowhere: QB rushing yards over four yards per carry. Let's say a QB rushes 100 times for 500 yards; I'll add 100 yards to his passing yards total, because he gained an additional 100 yards over four yards per carry. If he rushed 200 times for 1,000 yards, he'll get 200 yards added to his passing yards total. The thinking here is that on a running play, an average team can pick up four yards; the QB only gets credit for the additional yards they get. What I like about this, is that QBs that don't run aren't penalized.

How does this idea work in practice? Remember the Best QB of All Time post? (Which needs to be updated; it's on my to-do list). Well I'm going to use that sort of logic. Here's the thinking:

1) Start with a QB's adjusted net yards per attempt. Adjusted yards per attempt, you might remember, is calculated by adding 10 yards for every TD pass and subtracting 45 yards for every interception, and dividing that number by pass attempts. To calculate adjusted net yards per attempt, we'll subtract sack yards lost from the numerator, and divide by [pass attempts plus sacks].

2) Now we want to add in rushing yards over 4.0, too. I don't think we want to call this net adjusted net yards per attempt; let's just call it yards per play for now. So our numerator which previously contained:

Passing Yards [plus] Passing TDs *10 [minus] Passing INTs * 45 [minus] Sack Yards lost

Will now also get rushing yards over 4.0 added to it (RYO4.0). And the denominator will stay the same. Here's the final formula to calculate yards per play:

(Passing Yards [plus] Passing TDs *10 [plus] RYO4.0 [minus] Passing INTs * 45 [minus] Sack Yards lost) / (Pass attempts + Sacks)

2) Then subtract the league average ANY/A from the individual QB's yards per play.

3) You now know how much value each QB added per attempt. Let's use an example.

Look at Daunte Culpepper in the year 2000. He attempted 474 passes and was sacked 34 times; so he had 508 total attempts. He passed for 3,937 yards and rushed for 470 yards on 89 attempts. He gained an extra 114 rushing yards over 4.0 yards per carry, so we'll add that to his passing yards, giving him 4051. He also threw for 33 TDs (+330 yards) and 16 INTs (-720 yards), for a total of 3,661 yards. Finally, he lost 181 yards due to sacks, giving him 3,480 yards. That's an average of 6.85 yards per play. In 2000, all QBs averaged 4.85 adjusted net yards per attempt. Therefore, Culpepper added two yards of value per play, so over his 508 plays, that's 1,018 yards (small difference due to rounding). So for the year 2000, Culpepper added 1,018 more yards than the average QB. Where does that rank among all black QBs? Here's the single season leaderboard:

Quarterback             team    year    Lgavg   Yd/Pl   Value
Daunte Culpepper	min	2004	5.23	7.45	1323
Randall Cunningham	min	1998	4.91	7.79	1279
Warren Moon		oti	1990	4.89	6.75	1148
Donovan McNabb		phi	2004	5.23	7.36	1070
Daunte Culpepper	min	2000	4.85	6.85	1018
Steve McNair		oti	2003	4.83	7.24	1008
Donovan McNabb		phi	2006	5.02	7.42	 810
Daunte Culpepper	min	2003	4.83	6.45	 796
Doug Williams		tam	1981	4.58	6.15	 766
Randall Cunningham	phi	1990	4.89	6.26	 704
David Garrard		jax	2007	5.11	7.12	 696
Steve McNair		oti	2001	4.82	6.16	 625
Michael Vick		atl	2002	4.97	6.29 	 597
Warren Moon		oti	1988	4.69	6.59	 582
Aaron Brooks		nor	2003	4.83	5.85	 565
Warren Moon		oti	1989	4.88	5.94	 528
Warren Moon		oti	1991	4.86	5.61	 509
Kordell Stewart		pit	2001	4.82	5.80	 460
Warren Moon		oti	1992	4.53	5.79	 454
Steve McNair		oti	1998	4.91	5.72	 423
Warren Moon		min	1995	5.04	5.67	 406
Doug Williams		tam	1980	4.45	5.18	 401

Here are their raw stats:

quarterback    	       ryo4.0	att    	pyd     ptd     int    	sack   	sackyd
Daunte Culpepper	 54	548	4717	39	11	46	238
Randall Cunningham	  4	425	3704	34	10	20	132
Warren Moon	          0	584	4689	33	13	36	252
Donovan McNabb	         56	469	3875	31	 8	32	192
Daunte Culpepper	114	474	3937	33	16	34	181
Steve McNair	          0	400	3215	24	 7	19	108
Donovan McNabb	         84	316	2647	18	 6	21	140
Daunte Culpepper	130	454	3479	25	11	37	196
Doug Williams	         17	471	3563	19	14	18	135
Randall Cunningham	470	465	3466	30	13	49	431
David Garrard	          0	325	2509	18	 3	20	 96
Steve McNair	        114	431	3350	21	12	37	251
Michael Vick	        325	421	2936	16	 8	33	206
Warren Moon	          0	294	2327	17	 8	12	120
Aaron Brooks	          0	518	3546	24	 8	34	195
Warren Moon	          0	464	3631	23	14	35	267
Warren Moon	          0	655	4690	23	21	23	174
Kordell Stewart	        153	442	3109	14	11	29	175
Warren Moon	         39	346	2521	18	12	16	105
Steve McNair	        251	492	3228	15	10	33	176
Warren Moon	          0	606	4228	33	14	38	277
Doug Williams	        138	521	3396	20	16	23	194

Regular readers of this blog won't be surprised to see 'Pepper top the list. His curious 2004 season was the subject of a still unsolved blog post from last June.

Final thoughts

  • I think rushing touchdowns and fumbles should factor into this as well, although I'm not 100% sure how. I'll consider that in a future post.

  • What do you guys think about rushing yards over 4.0? Should it be over 3.0? Is 4.0 too high? Alternatively, should the whole idea be scratched? Isn't a QB that runs 100 times for 300 yards still more valuable than one that runs 100 times for 100 yards? But if we look at all the rushing data, how do we avoid penalizing Peyton Manning and Dan Marino for taking lots of kneeldowns in their careers? Is it a reasonable assumption to say that every QB takes the same number of kneeldowns per pass attempt? I don't think so.
  • Randy Moss was on the top two, and three of the top five teams that had the best seasons by a black QB ever. If I recall correctly, his QB did pretty well this year, too. Terrell Owens was on another one of the top five teams, and his QBs always seem to do okay, too.
  • David Garrard had a really strong year. He didn't have that many attempts, and the league average was a bit better this year, but he wasn't too far off Culpepper's 2004 pace. PFR readers already know, however, that Garrard was off to a terrific start in 2007.

This entry was posted on Friday, February 8th, 2008 at 5:58 am and is filed under History, Statgeekery. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.