## Guest Post: Adam Steele: Adjusted Points Per Drive: QB Edition

Adam Steele is back for another guest post. You can view all of Adam’s posts here. As always, we thank him for contributing.

Previously, I introduced my new metric — Adjusted Points Per Drive — for measuring team offense. I thought it would be fun to apply the same methodology to quarterbacks, which I what I’m doing today. I highly encourage you to go back and read the previous post if you haven’t already, because I don’t want to clutter today’s post by repeating all of the calculation details.

Unfortunately, I don’t have drive stats for individual games, so there’s going to be some approximation here. To calculate a quarterback’s career Adjusted Points Per Drive (AjPPD), I simply take his team’s AjPPD from each of his playing seasons and weight those seasons by games started. This will give us a measure of a quarterback’s scoring efficiency, but it doesn’t account for volume or longevity. That’s where Adjusted Offensive Points (AjPts) comes in handy.

I assign each QB a portion of his teams’ Adjusted Points, then compare that to league average to calculate Points Over Average (POA). The formula for calculating a given season’s POA = (Tm AjPts – 315) * (GS / 16). The 315 figure is derived from multiplying my normalized baselines of 1.75 AjPPD by 180 drives per year, meaning the average team scores 315 Adjusted Points per season.

I’ll use Ben Roethlisberger’s 2015 season as an example: Pittsburgh scored 400 Adjusted Points and Ben started 11 games, so his 2015 campaign is worth (400 – 315) * (11 / 16) = 30 POA. Do this for every season and we have Career POA, which is the primary metric I’ll be using here. However, some people prefer to rank quarterbacks based on their peak years rather than their entire career, so I added the “Peak” column which is the sum of each quarterback’s three best POA seasons.

This study includes all QB’s who started their first game in 1997 or later, and made at least 40 starts between 1997 and 2015 (partial numbers from 2016 are not included). These criteria leaves us with 56 quarterbacks. Before we dig into the results, it’s worth noting that the correlation between Career POA and ANY/A+ is a healthy 0.92. We all know that the NFL is a passing league, but drive efficiency is even more dominated by the passing game than I thought. According to r2, 85% of the variance in Adjusted Points Per Drive is explained by a basic measure of passing efficiency. That doesn’t leave much room for the running game to have an impact. In fact, I’ll go as far to say that rushing efficiency has no appreciable impact on scoring for the majority of teams. That’s not to say running the ball is useless; offenses must run occasionally to keep the defense honest, and running comes in handy for converting short yardage and bleeding the clock. But, to quote Ron Jaworski, “Points come out of the passing game!”

Time for the rankings…

RankQuarterbackGSAjPPDPOAPeakANY/A+
1Peyton Manning2652.3981931601120
2Drew Brees2162.2561230437115
4Philip Rivers1602.133689384113
5Trent Green1132.198570417112
6Aaron Rodgers1192.167558388121
7Kurt Warner1162.172551542116
8Tony Romo1272.054435273116
9Daunte Culpepper1002.07360401107
10Matt Ryan1261.966306169106
11Ben Roethlisberger1691.905295176111
12Jeff Garcia1161.921223313112
13Cam Newton781.984205188103
14Eli Manning1831.844193174103
15Matt Schaub921.933189182108
16David Garrard761.919144142102
17Russell Wilson641.943139129115
18Carson Palmer1591.889232107
19Andrew Luck551.8757797102
20Donovan McNabb1611.79377139106
21Michael Vick1141.8016510298
22Brian Griese831.81763156101
23Matthew Stafford931.80557106101
25Matt Hasselbeck1601.76629245100
26Andy Dalton771.756565103
27Joe Flacco1221.741-129399
28Jake Delhomme961.735-16103103
29Kordell Stewart821.727-2113092
30Byron Leftwich501.687-3525100
31Colin Kaepernick471.66-47-14101
32Marc Bulger951.697-57140102
33Jay Cutler1341.706-66149101
34Jay Fiedler601.641-7418100
35Jake Plummer1361.698-7916097
36Vince Young501.605-812094
37Jon Kitna1241.69-849595
38Charlie Batch551.607-891898
39Ryan Tannehill641.618-95-5493
40Aaron Brooks901.653-9847101
41Josh Freeman611.606-992894
42Jason Campbell791.612-1231497
43Rex Grossman471.488-139-390
44Matt Cassel781.584-1455692
46Josh McCown571.472-178-391
47Derek Anderson451.376-189-693
49Ryan Fitzpatrick1051.576-2051995
50Mark Sanchez721.496-206-4489
51Tim Couch591.431-212-6489
52Alex Smith1211.577-2351396
53Kyle Boller471.278-249-6582
54Kyle Orton821.425-300-2798
55David Carr791.412-300-4686
56Joey Harrington761.313-374-14387

There’s not much left to say about Peyton Manning’s greatness that hasn’t already been said, so I’ll just give you one amazing stat: Manning’s offenses have scored more points above average than the offenses of Tom Brady and Aaron Rodgers combined. The top five rounds out with Brees, Brady, still-criminally-underrated Philip Rivers, and…Trent Green? It’s safe to say that Green was a good QB, very good if we’re being generous, but he was never truly great. Green’s offenses were the exception to the rule; with Priest Holmes, Tony Gonzalez, and the most dominant offensive line of the 21st century, those Chiefs teams used the running game as their primary weapon, with Green’s passing providing a strong compliment. This is the squad that scored eight (!) rushing TD’s in a single game during their 2004 demolition of the Falcons. Speaking of rushing, the offenses of Cam Newton and Michael Vick significantly outperform what we’d expect from their ANY/A+, in large part due to the historical running prowess provided by these two unique players. The other notable overachiever is Eli Manning, which jives with the common sentiment that he plays better than his stats would indicate.

The most surprising result of this exercise is the lack of surprises. Most of the QB’s spent their career leading offenses that produce points in lockstep with their passing efficiency, so there doesn’t appear to be any secret sauce in scoring points that isn’t accounted for with basic passing stats. Frankly, this is a welcome result for us analytical types, as it validates the robustness of the passing metrics we like to employ in our studies.

What stands out to you? Is there anything else you’d like to see me do with this data?

{ 8 comments }
• sacramento gold miners

I think it’s extremely difficult to rate QBs under any system because they played under different conditions. Having your home games indoors a a built-in advantage some QBs enjoyed over others. And it’s not just the weather, old Texas Stadium had an issue with shadows which affected receivers.

For sure, it’s impossible to separate QB’s from their teammates and environment. The point of this study was to show that team PPD measures nearly the same thing as “individual” passing stats, which proves your point that entanglement is unavoidable.

• “it’s worth noting that the correlation between Career POA and ANY/A+ is a healthy 0.92”

But this is among the 56 quarterbacks who started at least 40 games, right? This is a biased sample as it filters out the vast majority of bad quarterbacks. If I’m understanding correctly what you did, then what we can conclude is: *among the top quarterbacks* scoring is driven overwhelmingly by passing — which is probably not that surprising.

Ron Jaworski’s quote might hold in a more general sense (I suspect it does), but I think you would need to look at all quarterbacks to validate such a claim.

Yes, the correlation only covers the 56 quarterbacks in this study. Why do you think bad QB’s have less impact on scoring? My thought is the Ryan Lindleys of the world negatively affect scoring in roughly the same proportion as great QB’s having a positive effect.

• Maybe it would, but maybe teams would rely more on the running game knowing that they have a bad quarterback, and so their scoring would be more driven by rushing success, and we wouldn’t see as strong a correlation between passing and scoring.

Consider a team like the 2012 Vikings with Christian Ponder at QB and Adrian Peterson at RB, would you expect that Ponder’s play would impact his team’s scoring in roughly the same way as Aaron Rodger’s play with Green Bay? I legitimately don’t know the answer. On the one hand, I’m inclined to say it wouldn’t because the Vikes could lean on AP and still score points; but on the other hand, maybe QB play is just that important no matter who is the supporting cast.

But my point is that you’ve filtered out cases like Ponder — this isn’t a huge criticism, by the way, more like a caveat that I think is worth mentioning.