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.

Sam Darnold — 2026 Every split →

Adj EPA / dropback
-0.038
Raw EPA / dropback
-0.051
Dropbacks
190
Turnover EPA
-40.5
WPA
-0.49
WeekOpp DropbacksAdj EPA/dbRaw EPA/dbScheduleTotal adj EPA INT / FLTurnover EPASacksSack EPAWPACPOE
1NE 3 -0.647 -0.692 +0.045 -1.9 0 / 0 +0.0 1 -2.1 -0.07 -24.2
3WAS 45 -0.005 +0.091 -0.096 -0.2 2 / 0 -13.5 0 +0.0 +0.18 +5.3
4LAC 25 -0.152 -0.207 +0.055 -3.8 1 / 0 -5.7 3 -1.8 -0.04 +0.3
5SF 34 -0.388 -0.354 -0.034 -13.2 2 / 0 -8.9 5 -7.5 -0.53 +0.1
6DEN 55 -0.030 -0.121 +0.091 -1.7 2 / 0 -6.8 5 -10.1 -0.25 -4.6
7KC 28 +0.487 +0.434 +0.053 +13.6 1 / 0 -5.6 0 +0.0 +0.22 +4.0
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 2026-10-28 11:05 UTC, from nflverse. Write-up: backtests/nfl_game_quality/FINDINGS.md.