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.

Ryan Tannehill — 2021

Adj EPA / dropback
+0.018
Raw EPA / dropback
+0.035
Dropbacks
603
Turnover EPA
-89.0
WPA
+1.00
WeekOpp DropbacksAdj EPA/dbRaw EPA/dbScheduleTotal adj EPA INT / FLTurnover EPASacksSack EPAWPACPOE
1ARI 41 -0.467 -0.480 +0.014 -19.1 1 / 2 -14.6 6 -20.8 -0.25 -6.6
2SEA 43 +0.154 +0.173 -0.019 +6.6 0 / 1 -5.5 3 -8.7 -0.04 +5.4
3IND 28 +0.133 +0.118 +0.015 +3.7 2 / 0 -9.1 1 -2.2 -0.08 +1.2
4NYJ 57 -0.110 +0.005 -0.115 -6.3 0 / 0 +0.0 7 -10.1 +0.13 -2.4
5JAX 25 +0.135 +0.263 -0.128 +3.4 0 / 0 +0.0 3 -4.1 +0.28 +0.2
6BUF 29 +0.320 +0.242 +0.078 +9.3 1 / 0 -4.4 0 +0.0 +0.43 +2.6
7KC 27 +0.504 +0.516 -0.013 +13.6 1 / 0 -4.8 1 -1.3 +0.25 +14.9
8IND 36 +0.231 +0.218 +0.014 +8.3 2 / 0 -4.9 3 -2.9 +0.43 +2.5
9LA 30 -0.045 -0.141 +0.097 -1.3 1 / 0 -3.5 3 -2.9 -0.04 +0.4
10NO 29 +0.187 +0.084 +0.103 +5.4 0 / 0 +0.0 2 -3.8 +0.09 +2.6
11HOU 54 -0.287 -0.185 -0.102 -15.5 4 / 0 -20.4 2 -2.1 -0.36 +3.8
12NE 23 -0.378 -0.409 +0.032 -8.7 1 / 0 -3.9 2 -3.4 -0.09 -13.2
14JAX 35 -0.111 +0.022 -0.133 -3.9 0 / 0 +0.0 4 -5.8 +0.06 -3.1
15PIT 36 -0.193 -0.240 +0.047 -7.0 1 / 0 -5.9 4 -6.1 -0.59 +5.2
16SF 33 +0.255 +0.235 +0.020 +8.4 0 / 0 +0.0 4 -5.3 +0.28 +11.9
17MIA 19 +0.139 +0.079 +0.060 +2.6 0 / 0 +0.0 1 -2.6 +0.03 +6.8
18HOU 33 +0.485 +0.568 -0.083 +16.0 0 / 0 +0.0 1 -2.4 +0.59 +7.9
20CIN 25 -0.199 -0.178 -0.021 -5.0 3 / 0 -12.1 1 -2.1 -0.12 -0.3
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.