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.
Josh Johnson — 2021
Adj EPA / dropback
+0.316
Raw EPA / dropback
+0.311
Dropbacks
88
Turnover EPA
-9.6
WPA
+0.28
| Week | Opp | Dropbacks | Adj EPA/db | Raw EPA/db | Schedule | Total adj EPA | INT / FL | Turnover EPA | Sacks | Sack EPA | WPA | CPOE |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 8 | CIN | 4 | -0.348 | -0.336 | -0.012 | -1.4 | 0 / 0 | +0.0 | 0 | +0.0 | -0.02 | -24.1 |
| 9 | IND | 43 | +0.354 | +0.336 | +0.019 | +15.2 | 1 / 0 | -5.3 | 2 | -3.0 | +0.03 | -3.0 |
| 16 | CIN | 41 | +0.341 | +0.349 | -0.008 | +14.0 | 1 / 0 | -4.3 | 1 | -1.1 | +0.27 | +7.3 |
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:
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.