Better Box Score Metrics: A New Look at Efficiency, Part 3

Introducing Player Efficiency Ratings (and a fix for Yards per Turn)

March 28, 2025 by Paul Würtztack in Analysis

If the WUL season has arrived, it means two things: my hibernation is over, and the WUL stats portal has expanded its menu. If last year set a new mark for the quality of data visualizations, this year rockets us to the future with the addition of Completions Above Expectations (Com+) and Receptions Above Expectations (Rec+), a machine-learning fueled approach to measuring relative player efficiency.

I haven’t yet had time to dive into Com+ and Rec+, but I am particularly intrigued because at this point in each of the last two years (here and here), I have started the new season with musings on measuring efficiency—“the often measurable ability to avoid making mistakes” as Wikipedia aptly frames it—and we’ll now make it three in a row. Compared to Com+/Rec+, we’ll be taking a lo-fi approach to efficiency, but that’s in keeping with BBSM’s orientation toward summary stats and a desire to be as uncomplicated as possible. Indeed, we’ll offer up a simple approach (that needs to be handled with caution), as well as a more involved approach that works through the issues one should be cautious about.