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.

Matthew Stafford — 2022

Adj EPA / dropback
-0.047
Raw EPA / dropback
-0.072
Dropbacks
332
Turnover EPA
-63.1
WPA
-0.41
WeekOpp DropbacksAdj EPA/dbRaw EPA/dbScheduleTotal adj EPA INT / FLTurnover EPASacksSack EPAWPACPOE
1BUF 48 -0.291 -0.349 +0.058 -14.0 3 / 0 -15.6 7 -11.3 -0.29 -0.6
2ATL 37 +0.099 +0.175 -0.076 +3.7 2 / 0 -11.0 1 -0.5 +0.02 +7.9
3ARI 26 +0.385 +0.389 -0.004 +10.0 0 / 0 +0.0 1 -2.2 +0.23 +6.2
4SF 55 -0.202 -0.233 +0.032 -11.1 1 / 1 -13.5 7 -11.5 -0.24 -1.6
5DAL 47 -0.223 -0.306 +0.083 -10.5 1 / 2 -14.9 5 -15.8 -0.37 -1.2
6CAR 34 +0.088 +0.090 -0.001 +3.0 1 / 0 -8.1 1 -2.3 +0.15 +8.3
8SF 35 +0.050 +0.012 +0.038 +1.8 0 / 0 +0.0 2 -4.3 +0.06 -5.5
9TB 31 -0.146 -0.151 +0.005 -4.5 0 / 0 +0.0 4 -5.6 -0.20 -13.5
11NO 19 +0.312 +0.238 +0.074 +5.9 0 / 0 +0.0 1 -2.2 +0.24 -1.3
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.