luckadjusted

Week 18 2023 · January 7, 2024

Bears at Packers, Week 18 2023: who deserved to win?

The Packers beat the Bears 17–9, and it was no fluke: replayed with the way both teams actually played, the Packers win 9 of 10. The Bears had the bounces: kicks alone were worth 19 points of win probability to the Bears.

Before kickoff the Packers were 57% favorites. The biggest swing (Q2, 4:01 left): the Bears converted 3rd & 4, worth 12 points of win probability to the Bears.

Final

Chicago Bears 9
Green Bay Packers 17

January 7, 2024 · Lambeau Field · Closing line: Packers −2.5

Luck index +10 Packers about even · −10 Bears

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. Bears win 1, Packers win 9.

  1. 1 CHI 22 GB 17
  2. 2 CHI 28 GB 31
  3. 3 CHI 20 GB 24
  4. 4 CHI 17 GB 24
  5. 5 CHI 27 GB 37
  6. 6 CHI 10 GB 21
  7. 7 CHI 20 GB 34
  8. 8 CHI 7 GB 23
  9. 9 CHI 0 GB 20
  10. 10 CHI 10 GB 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

Bears win 10% of them, Packers 90%, counting the 2% still level after regulation as half each. The line is what actually happened: Packers by 8.

Show as a table
Final margin in the replaysShare of replays
Bears by 17+0.1%
Bears by 9–161.3%
Bears by 1–86.8%
Level after regulation2.0%
Packers by 1–821.0%
Packers by 9–1629.3%
Packers by 17+39.6%

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 +1.1 points to the Bears: the final margin was Packers by 8, without the luck Packers by 9.1. 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.

  • C. Santos, 50 yds made · 68% expected
  • A. Carlson, 41 yds missed · 83% expected
  • C. Santos, 39 yds made · 87% expected
  • C. Santos, 35 yds made · 92% expected
  • A. Carlson, 25 yds made · 97% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Bears 1 for 10 yards, Packers 1 for 5 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
Q4 7:56 Defensive Offside on the Packers (Rashan Gary), 5 yards · pre-snap +7% CHI +2.4 pts
Q4 7:17 Offensive Holding on the Bears, 10 yards +4% GB +1.2 pts

Bears penalties, every game · Packers penalties, every game · All teams, 2023

When it happened

Packers’ chance of winning

As low as 38% 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 Packers were ahead in it, below while the Bears were.
#WhenWhat happenedWin probability forNext drive
1 Q1 8:59 C. Santos made 50-yard field goalKicks · 68% expected for him, 26 of 37 from 45+ before +6% CHI CHI: Punt
2 Q1 2:39 A. Carlson missed 41-yard field goalKicks · 83% expected for him +11% CHI GB: Touchdown
3 Q2 15:00 The Bears were stopped on 3rd & 63rd & 4th downs · 37% expected +7% GB CHI: Punt
4 Q2 4:01 The Bears converted 3rd & 43rd & 4th downs · 46% expected +12% CHI CHI: Field goal
5 Q2 2:00 The Bears were stopped on 3rd & 63rd & 4th downs · 37% expected +10% GB CHI: Field goal
6 Q3 9:52 The Packers converted 3rd & 33rd & 4th downs · 56% expected +7% GB GB: Touchdown
7 Q3 1:24 The Packers were stopped on 3rd & 23rd & 4th downs · 64% expectedThe Packers fumbled and the Bears recoveredFumble bounces · loose balls are close to 50/50 +11% CHI GB: Field goal
8 Q4 7:56 Defensive Offside on the Packers (Rashan Gary), 5 yardsPre-snap flags · 9 flags in 2575 snaps before, position avg 1 per 444 +7% CHI CHI: Punt

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 Watson (GB WR), out · 0.7 pts
  • Eric Stokes (GB CB), out (IR) · 0.4 pts
  • Isaiah McDuffie (GB LB), out · 0.1 pts
  • Jaylon Johnson (CHI CB), out · 0.9 pts
  • Darnell Mooney (CHI WR), out · 0.8 pts
  • Yannick Ngakoue (CHI DE), out (IR) · 0.7 pts
  • Lucas Patrick (CHI C), out (IR) · 0.4 pts
  • D'Onta Foreman (CHI RB), out · 0.1 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

Bears 1% · Packers 99%

Final margin
Packers by 8
Luck in points
1.1 for the Bears
Luck-adjusted margin
Packers by 9.1
Replay with same day's form
Bears 10% · Packers 90% 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 18 2023 games · Bears · Packers

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