luckadjusted

Week 4 2020 · October 4, 2020

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

Colts at Bears, Week 4 2020: who deserved to win?

The Colts beat the Bears 19–11 and were the better team on the day: replayed with the same form, they win 6 of 10.

Before kickoff the Colts were 60% favorites. The biggest swing (Q1, 10:11 left): the Colts converted 3rd & 9, worth 14 points of win probability to the Colts.

Final

Indianapolis Colts 19
Chicago Bears 11

October 4, 2020 · Soldier Field · Closing line: Colts −3.5

Luck index +40 Colts lucky · −40 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. Colts win 6, Bears win 4.

  1. 1 IND 24 CHI 0
  2. 2 IND 25 CHI 10
  3. 3 IND 31 CHI 19
  4. 4 IND 32 CHI 24
  5. 5 IND 26 CHI 21
  6. 6 IND 32 CHI 30
  7. 7 IND 10 CHI 12
  8. 8 IND 24 CHI 30
  9. 9 IND 20 CHI 31
  10. 10 IND 19 CHI 37

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

Colts win 60% of them, Bears 40%, counting the 3% still level after regulation as half each. The line is what actually happened: Colts by 8.

Show as a table
Final margin in the replaysShare of replays
Colts by 17+14.1%
Colts by 9–1617.2%
Colts by 1–827.5%
Level after regulation2.8%
Bears by 1–820.5%
Bears by 9–1612.1%
Bears by 17+5.9%

Where the luck was

Take the luck out

The final margin was Colts by 8. Remove the luck, one kind at a time, and it becomes Colts by 3.2.

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.

  • C. Santos, 27 yds made · 96% expected
  • R. Blankenship, 21 yds made · 99% expected
  • R. Blankenship, 30 yds made · 96% expected
  • R. Blankenship, 44 yds made · 80% expected
  • R. Blankenship, 30 yds made · 96% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

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 Colts were.
#WhenWhat happenedWin probability forNext drive
1 Q1 10:11 The Colts converted 3rd & 93rd & 4th downs · 27% expected +14% IND IND: Touchdown
2 Q1 8:15 The Colts converted 3rd & 53rd & 4th downs · 38% expected +8% IND IND: Touchdown
3 Q2 8:45 The Colts converted 3rd & 73rd & 4th downs · 31% expected +5% IND IND: Field goal
4 Q2 7:49 Horse Collar Tackle on the Bears (Robert Quinn), 15 yardsJudgment calls · 3 flags in 765 snaps before, position avg 1 per 395 +6% IND IND: Field goal
5 Q2 3:50 R. Blankenship made 21-yard field goalKicks · 99% expected for him +6% CHI IND: Field goal
6 Q3 13:41 The Colts were stopped on 3rd & 13rd & 4th downs · 71% expected +6% CHI IND: Punt
7 Q4 12:32 Defensive Pass Interference on the Colts (Khari Willis), 32 yardsJudgment calls · 1 flag in 848 snaps before, position avg 1 per 510 +6% CHI CHI: Turnover
8 Q4 11:10 The Bears were stopped on 3rd & 103rd & 4th downs · 26% expected +5% IND 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.

  • T.J. Carrie (IND CB), out · 0.4 pts
  • Malik Hooker (IND FS), out (IR) · 0.4 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

Colts 63% · Bears 37%

Final margin
Colts by 8
Luck in points
4.8 for the Colts
Luck-adjusted margin
Colts by 3.2
Replay with same day's form
Colts 60% · Bears 40% 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 4 2020 games · Colts · Bears

More from Week 4 2020