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.

Malik Willis — 2022

Adj EPA / dropback
-0.565
Raw EPA / dropback
-0.547
Dropbacks
71
Turnover EPA
-12.6
WPA
-1.54
WeekOpp DropbacksAdj EPA/dbRaw EPA/dbScheduleTotal adj EPA INT / FLTurnover EPASacksSack EPAWPACPOE
2BUF 4 -0.429 -0.485 +0.056 -1.7 0 / 0 +0.0 0 +0.0 +0.00 -41.8
8HOU 13 -0.855 -0.817 -0.038 -11.1 1 / 0 -6.4 3 -4.2 -0.22 +1.7
9KC 19 -0.310 -0.293 -0.017 -5.9 0 / 0 +0.0 3 -2.7 -0.52 -21.8
13PHI 4 -0.730 -0.773 +0.044 -2.9 0 / 0 +0.0 0 +0.0 -0.00 -19.0
15LAC 4 -0.088 -0.101 +0.013 -0.4 0 / 0 +0.0 0 +0.0 -0.01 -0.5
16HOU 27 -0.672 -0.638 -0.034 -18.1 2 / 0 -6.2 4 -5.2 -0.79 -3.8
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.