Week 2 Bayesian Quarterback Rankings

Adjusted Quarterback Efficiency (AQE) going back to 2019 is now part of the most well calibrated projections

The big, fundamental change to the rankings this season is the integration of Adjusted Quarterback Efficiency (AQE) numbers. This produces rankings that align more closely to what the typical football observer or data-based analysts would assign based on a combination of observation and statistics.

For the Week 1 projection, I weaved the AQE figures for 2023 and 2022 into the mix. This week I discovered the addition of prior years’ charting from FTNData, enabling us to go back to 2019 and calculate AQE. Because we’re shifting the historical data for several years in the new projections, the projection movement from Week 1 wouldn’t be primarily based on last week’s quarterback performances, but mostly on revisions to 2019-2021 efficiencies.

You can find all the previous weekly editions of the Bayesian Quarterback Rankings here, and the backlog for Adjusted Quarterback Efficiency is 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 plot below is a bit different than previous iterations of this post, substituting AQE for unadjusted EPA per play, and you might notice that the data has less dispersion (i.e. something like a higher r²) than using straight EPA. Even so, AQE doesn’t perfectly align with PFF grading, and you can decide which measure is more representative of fundamental quarterback play. (hint: it’s AQE!)

Details on the movement between unadjusted EPA per play and AQE are on the plot below. Compared to PFF grading, the drop in Baker Mayfield’s efficiency puts his numbers almost perfectly aligned with the trend-line. On the flip side, the AQE position adjustments move Brock Purdy and Aaron Rodgers from below the trend line to far above. The same can be said for Joe Burrow, though he’s a bit down the pecking order by both metrics.

Unlike PFF grading, AQE isn’t buying the idea that Deshaun Watson played at a respectable level, and it’s lower on the performance of Tua Tagovailoa, who generated a ton of value via YAC.