luckadjusted
NFL Week 9 · 2026

Week 16 2024 · December 22, 2024

Lions at Bears, Week 16 2024: who deserved to win?

The Lions beat the Bears 34–17, and the replays back it up: with the way both teams actually played, the Lions win 10 of 10.

Before kickoff the Lions were 70% favorites.

Final

Detroit Lions 34
Chicago Bears 17

December 22, 2024 · Soldier Field · Closing line: Lions −7

Luck index +2 Lions about even · −2 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. Lions win 10, Bears win 0.

  1. 1 DET 44 CHI 7
  2. 2 DET 37 CHI 7
  3. 3 DET 43 CHI 17
  4. 4 DET 30 CHI 7
  5. 5 DET 34 CHI 14
  6. 6 DET 41 CHI 24
  7. 7 DET 38 CHI 24
  8. 8 DET 24 CHI 13
  9. 9 DET 38 CHI 31
  10. 10 DET 17 CHI 14

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

Lions win 98% of them, Bears 2%. The line is what actually happened: Lions by 17.

Show as a table
Final margin in the replaysShare of replays
Lions by 17+79.6%
Lions by 9–1613.4%
Lions by 1–85.2%
Level after regulation0.4%
Bears by 1–81.0%
Bears by 9–160.3%
Bears by 17+0.0%

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 +0.3 points to the Lions: the final margin was Lions by 17, without the luck Lions by 16.7. 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.

  • J. Bates, 30 yds made · 96% expected
  • J. Bates, 34 yds made · 93% expected
  • J. Bates, 65 yds missed · 27% expected
  • C. Santos, 30 yds made · 96% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Lions 7 for 55 yards, Bears 10 for 70 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 half toward luck; pre-snap fouls, which repeat, don’t count. How calls are valued

WhenFlagWin probability for
Q1 13:17 Taunting on the Lions (Jameson Williams), 15 yards +4% CHI +1.4 pts
Q1 9:29 Defensive Offside on the Lions (Pat O'Connor), 5 yards · pre-snap +2% CHI +0.6 pts
Q1 4:47 Offensive Holding on the Bears (D.J. Moore), 10 yards +2% DET +0.9 pts
Q2 15:00 Offensive Holding on the Bears, 10 yards +3% DET +1.3 pts
Q2 11:35 False Start on the Bears, 5 yards · pre-snap +1% DET +0.6 pts
Q2 8:19 False Start on the Bears (Gerald Everett), 5 yards · pre-snap +1% DET +0.7 pts
Q2 2:02 Neutral Zone Infraction on the Bears (Austin Booker), 5 yards · pre-snap +1% DET +1.8 pts
Q2 0:01 False Start on the Lions, 5 yards · pre-snap +1% CHI +0.3 pts
Q3 13:00 Unsportsmanlike Conduct on the Bears (Jaylon Johnson), 15 yards +1% DET +1.8 pts
Q3 10:30 Offensive Offside on the Bears (Keenan Allen), 5 yards · pre-snap 0% DET +0.9 pts
Q4 12:44 False Start on the Bears, 5 yards · pre-snap +1% DET +0.7 pts
Q4 10:27 Defensive Too Many Men on Field on the Lions, 5 yards · pre-snap 0% CHI +0.5 pts
Q4 9:09 False Start on the Bears, 5 yards · pre-snap 0% DET +0.8 pts
Q4 8:21 Delay of Game on the Bears, 5 yards · pre-snap 0% DET +0.3 pts
Q4 6:39 False Start on the Lions, 5 yards · pre-snap 0% CHI +0.9 pts
Q4 3:25 Unnecessary Roughness on the Lions (Za'Darius Smith), 15 yards 0% CHI +1.3 pts
Q4 3:18 Illegal Use of Hands on the Lions (Al-Quadin Muhammad), 5 yards 0% DET +0.1 pts

Lions penalties, every game · Bears penalties, every game · All teams, 2024

When it happened

Bears’ chance of winning

As low as 0% and as high as 55%. 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 Bears were ahead in it, below while the Lions were.
#WhenWhat happenedWin probability forNext drive
1 Q1 13:17 Taunting on the Lions (Jameson Williams), 15 yardsJudgment calls · 3 flags in 1319 snaps before, position avg 1 per 409 +4% CHI CHI: Turnover
2 Q1 9:44 The Lions were stopped on 3rd & 33rd & 4th downs · 59% expected +3% CHI DET: Field goal
3 Q1 8:31 The Bears fumbled and the Lions recoveredFumble bounces · loose balls are close to 50/50 +7% DET CHI: Turnover
4 Q1 7:02 The Lions converted 3rd & 63rd & 4th downs · 36% expected +5% DET DET: Touchdown
5 Q1 3:41 The Bears fumbled and the Lions recoveredFumble bounces · loose balls are close to 50/50 +4% DET CHI: Punt
6 Q1 0:10 The Lions were stopped on 3rd & 63rd & 4th downs · 44% expected +3% CHI DET: Field goal
7 Q1 0:06 J. Bates made a 34-yard field goalKicks · 93% expected for him +3% DET DET: Touchdown
8 Q2 9:18 The Bears converted 4th & 33rd & 4th downs · 52% expected +3% CHI CHI: Touchdown

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.

  • Kiran Amegadjie (CHI T), out · 0.3 pts
  • Ryan Bates (CHI C), out (IR) · 0.2 pts
  • Andrew Billings (CHI DT), out (IR) · 0.2 pts
  • Carlton Davis (DET CB), out (IR) · 0.7 pts
  • Graham Glasgow (DET G), out · 0.4 pts
  • Alim McNeill (DET DT), out (IR) · 0.4 pts
  • Alex Anzalone (DET LB), out (IR) · 0.3 pts
  • Malcolm Rodriguez (DET 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

Lions 100% · Bears 0%

Final margin
Lions by 17
Luck in points
0.3 for the Lions
Luck-adjusted margin
Lions by 16.7
Replay with same day's form
Lions 98% · Bears 2% unchanged: why
How much of each is luck?

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

What counts

None by default: our tests measured no carryover after a lucky break. Slide it up to count a break for more than its own swing. 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 16 2024 games · Lions · Bears

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