Game quality
How well each team played, beyond the score: EPA (expected points added) per play, adjusted for the opponent. A big day against a bad defence counts for less. Season views include playoff games.
Brett Rypien — 2023 Every split →
Adj EPA / dropback
-0.500
Raw EPA / dropback
-0.493
Dropbacks
40
Turnover EPA
-9.6
WPA
-0.26
| Week | Opp | Dropbacks | Adj EPA/db | Raw EPA/db | Schedule | Total adj EPA | INT / FL | Turnover EPA | Sacks | Sack EPA | WPA | CPOE |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 8 | DAL | 11 | -0.441 | -0.466 | +0.025 | -4.9 | 0 / 0 | +0.0 | 1 | -1.4 | -0.02 | -22.6 |
| 9 | GB | 29 | -0.523 | -0.503 | -0.020 | -15.2 | 1 / 1 | -9.6 | 1 | -6.4 | -0.25 | -17.6 |
How the ratings are built
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 2026-11-07 11:05 UTC, from nflverse. Write-up:
backtests/nfl_game_quality/FINDINGS.md.