luckadjusted

Week 9 2024 · November 3, 2024

Dolphins at Bills, Week 9 2024: who deserved to win?

The Bills beat the Dolphins 30–27, and it was no fluke: replayed with the way both teams actually played, the Bills win 8 of 10. The Dolphins had the bounces: judgment calls alone were worth 13 points of win probability to the Dolphins.

Before kickoff the Bills were 68% favorites. The biggest swing (Q4, 0:10 left): T. Bass made 61-yard field goal, worth 22 points of win probability to the Bills.

Final

Miami Dolphins 27
Buffalo Bills 30

November 3, 2024 · New Era Field · Closing line: Bills −6.5

Luck index +17 Bills about even · −17 Dolphins

Each team’s own plays from this game, resampled into new drives 4,000 times: with the way both teams actually played, how often does this performance win? How the replay works

Ten replays. Dolphins win 2, Bills win 8.

  1. 1 MIA 31 BUF 20
  2. 2 MIA 17 BUF 14
  3. 3 MIA 7 BUF 9
  4. 4 MIA 17 BUF 21
  5. 5 MIA 24 BUF 31
  6. 6 MIA 17 BUF 26
  7. 7 MIA 17 BUF 29
  8. 8 MIA 9 BUF 24
  9. 9 MIA 0 BUF 19
  10. 10 MIA 7 BUF 35

Three other ways to ask

Each answers a different question, so none of them replaces the replay above.

The closing betting line, turned into a probability. What everyone knew before the game.

The line plus what this game showed, weighted by how much one game can tell. It stays close to the line because one game says little.

Every kick, fumble bounce, drop, conversion and judgment call redrawn; everything else fixed. The narrowest view of luck.

How 4,000 replays ended

Dolphins win 17% of them, Bills 83%, counting the 2% still level after regulation as half each. The line is what actually happened: Bills by 3.

Show as a table
Final margin in the replaysShare of replays
Dolphins by 17+1.4%
Dolphins by 9–164.8%
Dolphins by 1–810.2%
Level after regulation2.2%
Bills by 1–826.9%
Bills by 9–1624.1%
Bills by 17+30.4%

Where the luck was

What the luck was worth

Every lucky and unlucky play, weighted by the moment it happened: its swing in win probability, added up by kind. A missed kick in a decided game counts for nothing; the same kick at the end of a tie game can be most of a win.

Swings add up across a game, so in one that went back and forth they can pass 100%. On the scoreboard the same luck was worth +0.6 points to the Bills: the final margin was Bills by 3, without the luck Bills by 2.4. Luck shares are the fitted ones (how much of each kind is luck).

The kicks

How likely each kicker was to make that kick (his own record, the distance and the weather), and what happened.

  • T. Bass, 40 yds made · 85% expected
  • J. Sanders, 39 yds made · 87% expected
  • T. Bass, 49 yds made · 70% expected
  • J. Sanders, 23 yds made · 98% expected
  • T. Bass, 61 yds made · 51% expected
  • Extra point missed · 93% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Dolphins 8 for 57 yards, Bills 4 for 40 yards

Every accepted flag, in order, and what it did to the helped team’s chance of winning at that moment, including any play it wiped out (points on the scoreboard in grey). A flag in a decided game is worth nothing; one at the turn of a close game can be worth most of a win. Judgment calls count toward luck, pre-snap fouls mostly don’t. How calls are valued

WhenFlagWin probability for
Q1 5:54 False Start on the Dolphins (Durham Smythe), 5 yards · pre-snap +3% BUF +0.9 pts
Q1 5:07 Unnecessary Roughness on the Bills (Taylor Rapp), 15 yards +5% MIA +2.3 pts
Q2 3:41 False Start on the Dolphins, 5 yards · pre-snap +2% BUF +0.5 pts
Q2 2:00 Defensive Pass Interference on the Dolphins (Cam Smith), 13 yards +2% BUF +0.8 pts
Q2 1:24 Defensive Holding on the Dolphins (Cam Smith), 5 yards +2% BUF +0.5 pts
Q2 0:41 Offensive Holding on the Bills, 10 yards +2% MIA +1.0 pts
Q2 0:35 Offensive Holding on the Bills, 10 yards, wiping out the play +19% MIA +4.8 pts
Q3 6:03 Defensive Offside on the Bills (Von Miller), 5 yards · pre-snap +7% MIA +0.9 pts
Q3 0:02 False Start on the Dolphins, 5 yards · pre-snap +2% BUF +0.7 pts
Q4 7:13 Defensive Holding on the Dolphins (Siran Neal), 4 yards +6% BUF +1.5 pts
Q4 0:54 Unnecessary Roughness on the Dolphins (Jordan Poyer), 15 yards +6% BUF +1.1 pts
Q4 0:54 Neutral Zone Infraction on the Dolphins (Chop Robinson), 5 yards · pre-snap +2% BUF +0.2 pts

Dolphins penalties, every game · Bills penalties, every game · All teams, 2024

When it happened

Bills’ chance of winning

As low as 25% and as high as 100%. Numbers mark the biggest luck moments, listed below.

nflfastR’s in-game win probability. It ignores the betting line, so it starts near even. Shaded above the middle while the Bills were ahead in it, below while the Dolphins were.
#WhenWhat happenedWin probability forNext drive
1 Q2 11:45 The Bills were intercepted on a well-placed throwInterceptions · 0% expected to stay out of the defense's hands +10% MIA BUF: Field goal
2 Q2 0:35 Offensive Holding on the Bills, 10 yards, wiping out the playJudgment calls +19% MIA MIA: End of half
3 Q3 7:24 The Bills converted 4th & 13rd & 4th downs · 68% expected +11% BUF BUF: Touchdown
4 Q4 14:07 The Dolphins were stopped on 3rd & 53rd & 4th downs · 42% expected +8% BUF MIA: Touchdown
5 Q4 13:28 The Dolphins converted 4th & 43rd & 4th downs · 46% expected +10% MIA MIA: Touchdown
6 Q4 2:34 The Dolphins converted 3rd & 73rd & 4th downs · 35% expected +12% MIA MIA: Touchdown
7 Q4 0:54 Unnecessary Roughness on the Dolphins (Jordan Poyer), 15 yardsJudgment calls · 14 flags in 6307 snaps before, position avg 1 per 462Neutral Zone Infraction on the Dolphins (Chop Robinson), 5 yardsPre-snap flags · 1 flag in 275 snaps before, position avg 1 per 445 +8% BUF BUF: Field goal
8 Q4 0:10 T. Bass made 61-yard field goalKicks · 51% expected for him, 33 of 48 from 45+ before +22% BUF –

Missing players

Key players (usually on the field for half the snaps or more) who missed this game or part of it, valued by position and quality. The same players are missing in every replay, so this counts as luck in points only.

  • Christian Benford (BUF CB), out · 0.8 pts
  • Zach Sieler (MIA DE), out · 0.7 pts
  • Jevon Holland (MIA SS), out · 0.5 pts
  • Kader Kohou (MIA CB), out · 0.5 pts
  • Jaelan Phillips (MIA LB), out (IR) · 0.2 pts

Adjust the assumptions

Disagree with how much of a fumble bounce or a pass interference call is luck? Change it and the coin-flip replay reruns in your browser.

Only coin-flips re-rolled

Dolphins 33% · Bills 67%

Final margin
Bills by 3
Luck in points
0.6 for the Bills
Luck-adjusted margin
Bills by 2.4
Replay with same day's form
Dolphins 17% · Bills 83% unchanged: why
How much of each is luck?

0% treats it as skill, 100% as pure luck. The tick is our fit.

What counts

We tested momentum on 19,000 lucky breaks and found none, so it's off by default. Why

Flip a play

Force the other outcome, in this game and in every replay: a made kick becomes a miss, a stop becomes a conversion, a flag goes the other way.

About these numbers

Play-by-play and win probability from nflfastR via nflverse; kicks valued against each kicker’s own record; drops and interception-worthy throws from FTN charting; injuries from snap counts and injury reports.

Methodology and validation · All Week 9 2024 games · Dolphins · Bills

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