Week 16 Bayesian Quarterback Rankings

Brock Purdy continues his ascent, Derek Carr and Jake Browning also on the rise

You can find all the previous weeks’ versions of the Bayesian Quarterback Rankings here.

COMPARING GRADES AND EFFICIENCY

PFF grades aren’t part of the analysis, but I find it helpful to make not of how they align with EPA per play, as many contextual elements of quarterback play (drops, interception-worthy throws, easier throws that become big gains, etc) are part of the grading methodology, but aren’t accounted for in EPA. At the same time, I think EPA does a vastly superior job of weighing what is and isn’t important in points-based results.

The EPA-base efficiency and grading rankings are consolidating around Josh Allen, Dak Prescott and Tua Tagovailoa around the top in both, with Brock Purdy pushing his way into the top-5 in PFF grading, from as low as the late teens midway through the season. Grades on Purdy have followed EPA, though they’re still way out of alignment versus other of quarterbacks.

It wasn’t to this extreme, but we have seen some Patrick Mahomes seasons with big misalignments in grading and EPA, most notable in 2021. Mahomes finished the 2021 regular season second in EPA per play, slightly behind Aaron Rodgers, but his PFF grading ranked 13th. In 2019 and 2020, Mahomes was also second in EPA, but fifth and fourth, respectively, in PFF grading.

This season, Mahomes’ grading is below the grade-epa trend-line for the first time ever, reflecting the lack of receiver talent and the league’s highest drop rate. Mahomes is so far ahead of the crowd in career EPA efficiency that it won’t affect his Bayesian ranking unless this continues for at least another full season.

You’ll see the exact rankings movements below, but the Week 15 relative performances show you why there were some movements near the top, and a lot in the middle of the pack. Dak Prescott had his second worst (slightly better than versus the 49ers) EPA performance of the season, and his grading was even worse, meaning it can’t be written off as a fluky result. I don’t make defense faced a big factor, but it’s at least noteworthy that the Bills had been poor in coverage for several weeks going into Week 15.

Lamar Jackson underperforming his grading, once again, though I don’t there’s as easy of an explanation as with Mahomes and drops. Jackson’s big-time throw and turnover-worthy play rates aren’t as good as his overall grading, meaning he must have fewer bad-not-awful plays and more good-not-great throws than other quarterbacks. Regardless, it appears the Ravens offense and Jackson aren’t deriving as much easy efficiency as you’d expect from his grading.

Also note the Week 15 performances for Derek Carr, Jake Browning and Aidan O’Connell, who all make movements up the middle of the rankings.

WEEK 16 PROJECTED EFFICIENCY

These results are the ranking for the go-forward projections of quarterback efficiency this season. I also included the EPA per play rankings for each quarterback over the last five seasons (minimum 250 dropbacks in previous years, 120 in 2023) so you can see the evidence going into the projections.

Older data is decayed over time, so the 2023 EPA per play data matters more than those from pre-2020. That said, older data can’t be fully discounted, or else you miss bounce-back performers of great quarterback returning to form, like Aaron Rodgers in 2020 and 2021.

This week we have early confirmation that Case Keenum will start in place of C.J. Stroud, who has a worrying, multi-week absence due to continuing concussion symptoms. The Falcons confirmed they’re turning back to Taylor Heinicke and the Steelers are starting Mason Rudolph. I’m keeping Zach Wilson in the rankings, not knowing at this point who will be behind center if he can’t go.