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ATVS Quarterback Productivity Index: Let's Look At the Numbers

On Friday, I introduced you (again) to the ATVS Quarterback Productivity Index.  It is an attempt to improve upon the traditional, but not terribly helpful, "Passer Rating".  It is measured in yards per attempt, with bonuses and penalties for interceptions and touchdowns, and includes quarterback rushing statistics as well.  Here is the formula:

Passer Rating = (yards passing + yards rushing - yards lost by sack + 5*(First down completions and runs) + 20*Number of Touchdowns - 30*Number of Turnovers)/(Number of pass attempts + rush attempts).

You should think of this as giving a value for how much yardage a quarterback is worth when his number is called, with bonuses and penalties.

I was asked by LSUJonno to take a look at some numbers.  I agreed, but there is one problem with that request.  One of the statistics I use to compile the index is not generally kept.  Without good statistics on 1st Downs, it is impossible to get a good indication of where the numbers are.  So, I calculated the numbers simply taking out the 1st down statistics.  This should make a dramatic impact on the absolute scale of numbers, as most quarterbacks will probably get 1st downs on approximately half of their completed passes.  With a 1st down being worth 5 bonus yards above and beyond the yardage actually gained, you can expect that the actual numbers using the full formula would be 1 to 2 yards higher than are given.

Also, please note, that according to ESPN statistics, no quarterback in the SEC lost a fumble, so that part of the formula washes out.

Before we take a look at the numbers, let's take a look at the perceptions.  If you ask most observers, they would say that in 2008, there were 3 top-tier quarterbacks in the SEC:  Tim Tebow of Florida, Matthew Stafford of Georgia, and Jevan Snead of Ole Miss.  After that, most would say that there was a second tier of John Parker Wilson of Bama and Casey Dick of Arkansas.  Then, there was a monstrous collection of suck throughout the conference.  Let's see if the numbers bear this out:

ATVSQBPI Ratings for 2008 SEC Quarterbacks:

Quarterback ATVSQBPI (y/play)
Tim Tebow, Florida 8.73
Matthew Stafford, Georgia 8.49
Jevan Snead, Ole Miss 7.84
John Parker Wilson, Bama 5.87
Casey Dick, Arkansas 5.68
Jarrett Lee, LSU 5.56
Chris Smelley, South Carolina 5.12
Jordan Jefferson, LSU 5.11
Nick Stephens, Tennessee 5.10
Kodi Burns, Auburn 5.02
Chris Nickson, Vandy 5.01
Stephen Garcia, South Carolina 4.95
Tyson Lee, Mississippi State 4.86
Mike Hartline, Kentucky 4.77
Jonathan Crompton, Tennessee 4.34
Mackenzi Adams, Vandy 4.03
Chris Todd, Auburn 4.02
Wesley Carroll, Mississippi State 2.85

Most of our initial prejudices appear to be born out.  There is definitely a first tier, and it includes the quarterbacks we would have expected.  Tebow, Stafford, and Snead, and no others.

While Casey Dick and John Parker Wilson were the next two quarterbacks, the second tier didn't quite develop as I would have expected.  Jarrett Lee is right there with him, and for that I think you can thank the fact that the formula I use does not distinguish between interceptions returned for a touchdowns and interceptions with no return.  After Lee, it is not all that far to the Smelleys and Burnses of the conference.

Also, it is important to realize that other than the top 3 quarterbacks on the list, almost no one had a very good TD/Int ratio.  Nine quarterbacks in the SEC threw more interceptions than touchdowns, and 4 had ratios pretty close to 1:1.  In the entire SEC, only the following QBs (among the ones with appreciable statistics) had a TD/Int ratio better than 1.5:1:  Tebow, Stafford, Snead, Nathan Dick, Jordan Jefferson, and Chris Nickson.  That's it.

I did not list the raw statistics, but another feature here is that every quarterbacks rating suffered as a result of their rushing statistics, which is not surprising considering "rushes" includes sacks as well as mad scrambles to escape a rush, which often result in very short gains.  The question becomes how much do the rushing statistics hurt each quarterback, and how are they relative to each other.  The unfortunate side effect is that quarterbacks who had a lot of designed runs suffered disproportionately, and probably unfairly.  Kodi Burns and Stephen Garcia especially saw their ratings suffer.

Tim Tebow's ratings did not suffer much for his running because he's just that darn good at it, and his touchdown numbers really kept him high up the list.

Jarrett Lee was easily the least effective rusher, failing to score a rushing touchdown and averaging a whopping 8.82 yard loss per rush.  The good news is that he did not have a lot of rushes, which means he did a good job of getting rid of the ball.  But then again, see his 16 interceptions.

It does verify what I told Team Speed Kills back when they were previewing LSU, which was that Jarrett Lee was not the worst QB in the conference.  In fact, statistically (both in passer ratings and in ATVSQBPI) he was towards the middle of the pack.  People just remember the returns, which weren't really his fault beyond the fact that he threw the interceptions.  But everyone threw interceptions except Tebow, Snead, Stafford, and Nickson.  Lee was not good, but there were a LOT of 'not good' quarterbacks in the SEC.  Among the 'not good' quarterbacks, Lee was actually one of the better ones, especially if you don't blame him for the fact that so many of his interceptions had big returns.

You can decide for yourself if those returns are his fault, beyond the mere fact that he threw the interception that led to the return.

It's too bad I could not add in the first down statistics, as it would have been interesting to see if they made a significant difference in how the quarterbacks ranked. 

Here is a link to the spreadsheet with the raw data if you're interested.

2008 Quarterback Statistics