luckadjusted

Week 15 2020 · December 20, 2020

No FTN charting for this game (drops and interception-worthy throws are not modelled).

Patriots at Dolphins, Week 15 2020: who deserved to win?

The Dolphins beat the Patriots 22–12 and were the better team on the day: replayed with the same form, they win 8 of 10. The Patriots had the bounces: kicks alone were worth 22 points of win probability to the Patriots.

Before kickoff the Patriots were 54% favorites. The biggest swing (Q2, 0:05 left): J. Sanders missed 52-yard field goal, worth 12 points of win probability to the Patriots.

Final

New England Patriots 12
Miami Dolphins 22

December 20, 2020 · Hard Rock Stadium · Closing line: Patriots −1.5

Luck index +24 Dolphins about even · −24 Patriots

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. Patriots win 2, Dolphins win 8.

  1. 1 NE 17 MIA 6
  2. 2 NE 6 MIA 3
  3. 3 NE 14 MIA 17
  4. 4 NE 27 MIA 31
  5. 5 NE 10 MIA 17
  6. 6 NE 6 MIA 15
  7. 7 NE 14 MIA 27
  8. 8 NE 12 MIA 27
  9. 9 NE 3 MIA 20
  10. 10 NE 10 MIA 34

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

Patriots win 24% of them, Dolphins 76%, counting the 4% still level after regulation as half each. The line is what actually happened: Dolphins by 10.

Show as a table
Final margin in the replaysShare of replays
Patriots by 17+2.5%
Patriots by 9–166.2%
Patriots by 1–815.3%
Level after regulation4.3%
Dolphins by 1–824.8%
Dolphins by 9–1624.8%
Dolphins by 17+22.1%

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 +7.5 points to the Patriots: the final margin was Dolphins by 10, without the luck Dolphins by 17.5. 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.

  • N. Folk, 45 yds made · 77% expected
  • N. Folk, 36 yds made · 91% expected
  • J. Sanders, 52 yds missed · 67% expected
  • N. Folk, 45 yds made · 78% expected
  • N. Folk, 42 yds made · 84% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Patriots 2 for 20 yards, Dolphins 7 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
Q2 14:11 Neutral Zone Infraction on the Dolphins (Andrew Van Ginkel), 5 yards · pre-snap 0% NE +0.5 pts
Q2 10:34 Defensive Holding on the Dolphins (Xavien Howard), 5 yards, wiping out the play +1% NE +0.2 pts
Q2 8:05 False Start on the Dolphins, 5 yards · pre-snap +1% NE +0.4 pts
Q3 14:25 Face Mask on the Patriots, 15 yards +6% MIA +1.8 pts
Q3 9:12 Offensive Holding on the Dolphins (Isaiah Ford), 10 yards +4% NE +1.7 pts
Q3 8:00 Illegal Touch Pass on the Dolphins (Kamu Grugier-Hill), 5 yards, wiping out the play +7% NE +1.7 pts
Q3 7:03 Illegal Contact on the Dolphins (Jerome Baker), 5 yards +3% NE +0.9 pts
Q4 15:00 Defensive Too Many Men on Field on the Patriots, 5 yards · pre-snap +4% MIA +0.8 pts
Q4 10:38 Illegal Contact on the Dolphins, 5 yards 0% NE +0.2 pts

Patriots penalties, every game · Dolphins penalties, every game · All teams, 2020

When it happened

Dolphins’ chance of winning

As low as 33% 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 Dolphins were ahead in it, below while the Patriots were.
#WhenWhat happenedWin probability forNext drive
1 Q1 0:04 The Dolphins were stopped on 3rd & 33rd & 4th downs · 42% expected +10% NE MIA: Punt
2 Q2 6:17 The Patriots converted 3rd & 63rd & 4th downs · 35% expected +7% NE NE: Field goal
3 Q2 0:11 The Dolphins converted 4th & 83rd & 4th downs · 30% expected +10% MIA MIA: Missed field goal
4 Q2 0:05 J. Sanders missed 52-yard field goalKicks · 67% expected for him, 22 of 30 from 45+ before +12% NE MIA: Touchdown
5 Q3 8:00 Illegal Touch Pass on the Dolphins (Kamu Grugier-Hill), 5 yards, wiping out the playJudgment calls · 2 flags in 836 snaps before, position avg 1 per 395 +7% NE NE: Field goal
6 Q3 0:44 The Dolphins converted 3rd & 83rd & 4th downs · 30% expected +10% MIA MIA: Touchdown
7 Q4 13:02 The Dolphins converted 3rd & 33rd & 4th downs · 42% expected +10% MIA MIA: Touchdown
8 Q4 11:15 The Patriots converted 3rd & 153rd & 4th downs · 19% expected +9% NE NE: Field goal

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.

  • DeVante Parker (MIA WR), out · 0.7 pts
  • Mike Gesicki (MIA TE), out · 0.7 pts
  • Preston Williams (MIA WR), out (IR) · 0.5 pts
  • Ereck Flowers (MIA G), out · 0.5 pts
  • Myles Gaskin (MIA RB), out (IR) · 0.1 pts
  • Isaiah Wynn (NE OL), out (IR) · 0.4 pts
  • Ryan Izzo (NE TE), out (IR) · 0.2 pts
  • Jermaine Eluemunor (NE G), out · 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

Patriots 0% · Dolphins 100%

Final margin
Dolphins by 10
Luck in points
7.5 for the Patriots
Luck-adjusted margin
Dolphins by 17.5
Replay with same day's form
Patriots 24% · Dolphins 76% 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 (not available for this game); injuries from snap counts and injury reports. No FTN charting for this game (drops and interception-worthy throws are not modelled).

Methodology and validation · All Week 15 2020 games · Patriots · Dolphins

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