Game quality

What each result was worth beyond the score. Every play is graded by EPA (expected points added), then adjusted for who it came against: a defence's rating is what it allowed to everyone else that season, so a big day against a bad defence counts for less. Season views include playoff games.

Desmond Ridder — 2022

Adj EPA / dropback
+0.043
Raw EPA / dropback
+0.037
Dropbacks
124
Turnover EPA
-5.6
WPA
-0.11
WeekOpp DropbacksAdj EPA/dbRaw EPA/dbScheduleTotal adj EPA INT / FLTurnover EPASacksSack EPAWPACPOE
15NO 30 -0.125 -0.194 +0.069 -3.7 0 / 0 +0.0 4 -3.6 -0.38 -19.5
16BAL 35 +0.076 +0.112 -0.037 +2.7 0 / 0 +0.0 2 -2.5 -0.13 +2.7
17ARI 27 -0.021 -0.007 -0.014 -0.6 0 / 0 +0.0 1 -1.8 +0.12 +3.5
18TB 32 +0.219 +0.206 +0.013 +7.0 0 / 1 -5.6 2 -7.2 +0.29 +6.8
Opponent adjustment. A unit's rating for a game is its average over its other games that season, blended with 16 games' worth of prior (league average plus half of last season's gap from it; 24 games for pass defence, which is noisier). Early in a season that leans on last year; by midseason it is mostly this year. Chosen by how well it predicts a held-out game: it cut that error by about a quarter against no shrinkage, and adjusted numbers agree between odd and even weeks more than raw ones do (team EPA margin r 0.52 → 0.55, defence 0.32 → 0.36, QB EPA/dropback 0.47 → 0.49, 2016–2025).
Win expectancy is a logistic fit of wins on EPA margin over 6,036 completed games (it names the winner 86.5% of the time). These describe what happened; one game is not a forecast. Play-by-play credits the quarterback with every sack and dropback, so a bad line shows up in his numbers. Seasons 2016–2026, built 2026-09-14 01:25 UTC, from nflverse. Write-up: backtests/nfl_game_quality/FINDINGS.md.