luckadjusted

Week 17 2022 · January 1, 2023

Rams at Chargers, Week 17 2022: who deserved to win?

The Chargers beat the Rams 31–10, and it was no fluke: replayed with the way both teams actually played, the Chargers win 9 of 10. The Rams had the bounces: judgment calls alone were worth 1.9 points to the Rams.

Before kickoff the Chargers were 68% favorites. The biggest swing (Q2, 10:38 left): the Rams were stopped on 3rd & 6, worth 16 points of win probability to the Chargers.

Final

Los Angeles Rams 10
Los Angeles Chargers 31

January 1, 2023 · SoFi Stadium · Closing line: Chargers −6.5

Luck index +13 Chargers about even · −13 Rams

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. Rams win 1, Chargers win 9.

  1. 1 LA 21 LAC 16
  2. 2 LA 17 LAC 20
  3. 3 LA 35 LAC 41
  4. 4 LA 17 LAC 24
  5. 5 LA 10 LAC 20
  6. 6 LA 10 LAC 23
  7. 7 LA 17 LAC 34
  8. 8 LA 7 LAC 27
  9. 9 LA 3 LAC 27
  10. 10 LA 0 LAC 29

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

Rams win 13% of them, Chargers 87%, counting the 1% still level after regulation as half each. The line is what actually happened: Chargers by 21.

Show as a table
Final margin in the replaysShare of replays
Rams by 17+1.0%
Rams by 9–162.5%
Rams by 1–88.4%
Level after regulation1.3%
Chargers by 1–820.0%
Chargers by 9–1626.1%
Chargers by 17+40.8%

Where the luck was

Take the luck out

The final margin was Chargers by 21. Remove the luck, one kind at a time, and it becomes Chargers by 12.3.

Each row takes one kind of luck out of the margin. Color shows which team it helped. Luck shares are the fitted ones (how much of each component is luck).

The kicks

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

  • M. Gay, 23 yds made · 99% expected
  • C. Dicker, 40 yds made · 89% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

When it happened

Chargers’ chance of winning

As low as 41% 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 Chargers were ahead in it, below while the Rams were.
#WhenWhat happenedWin probability forNext drive
1 Q1 13:00 The Rams were stopped on 3rd & 43rd & 4th downs · 48% expected +7% LAC LA: Punt
2 Q1 9:52 Offensive Holding on the Chargers (Donald Parham), 9 yardsJudgment calls · 7 flags in 800 snaps before, position avg 1 per 282 +5% LA LA: Field goal
3 Q1 7:57 The Rams converted 3rd & 53rd & 4th downs · 43% expected +4% LA LA: Field goal
4 Q1 3:29 The Rams converted 3rd & 43rd & 4th downs · 48% expected +5% LA LA: Field goal
5 Q2 10:38 The Rams were stopped on 3rd & 63rd & 4th downs · 39% expectedIntentional Grounding on the Rams (Baker Mayfield), 12 yardsJudgment calls · 9 flags in 3627 snaps before, position avg 1 per 697 +16% LAC LA: Punt
6 Q2 9:58 The Chargers converted 3rd & 73rd & 4th downs · 37% expected +4% LAC LAC: Touchdown
7 Q2 4:14 The Rams converted 3rd & 33rd & 4th downs · 54% expected +6% LA LA: Touchdown
8 Q3 6:15 The Rams were stopped on 3rd & 43rd & 4th downs · 48% expectedThe Rams fumbled and the Chargers recoveredFumble bounces · loose balls are close to 50/50 +8% LAC LA: 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.

  • Derwin James (LAC FS), out · 0.7 pts
  • Christian Covington (LAC NT), out (IR) · 0.1 pts
  • Matthew Stafford (LA QB), out (IR), replaced by b.mayfield · 2.7 pts
  • Cooper Kupp (LA WR), out (IR) · 1.1 pts
  • Aaron Donald (LA DT), out · 0.9 pts
  • Allen Robinson (LA WR), out (IR) · 0.8 pts
  • Ben Skowronek (LA WR), out · 0.4 pts
  • Brian Allen (LA C), out · 0.3 pts
  • A'Shawn Robinson (LA DT), 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

Rams 0% · Chargers 100%

Final margin
Chargers by 21
Luck in points
8.7 for the Chargers
Luck-adjusted margin
Chargers by 12.3
Replay with same day's form
Rams 13% · Chargers 87% 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 17 2022 games · Rams · Chargers

More from Week 17 2022