luckadjusted

Week 1 2019 · September 8, 2019

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

Falcons at Vikings, Week 1 2019: who deserved to win?

The Vikings beat the Falcons 28–12, but the Falcons played well enough to win it: they take 7 of 10 replays with the same day's form.

The Vikings won on an off day: they played far below what the matchup promised. In a fresh game against the Falcons they would win 72% of the time; with this day’s form, 26%. The numbers

Before kickoff the Vikings were 60% favorites. The biggest swing (Q1, 12:59 left): Blocked punt by the Vikings, worth 11 points of win probability to the Vikings.

Final

Atlanta Falcons 12
Minnesota Vikings 28

September 8, 2019 · U.S. Bank Stadium · Closing line: Vikings −3.5

Luck index +74 Vikings very lucky · −74 Falcons

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. Falcons win 7, Vikings win 3.

  1. 1 ATL 35 MIN 7
  2. 2 ATL 30 MIN 10
  3. 3 ATL 24 MIN 10
  4. 4 ATL 24 MIN 13
  5. 5 ATL 24 MIN 17
  6. 6 ATL 24 MIN 20
  7. 7 ATL 21 MIN 19
  8. 8 ATL 14 MIN 17
  9. 9 ATL 17 MIN 25
  10. 10 ATL 13 MIN 31

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.

The Vikings won on an off day

They played far below what the matchup promised. In a fresh game against the Falcons they would win 72% of the time; with this day’s form, 26%.

47 points apart for the Vikings: the gap is how differently this game went from what the two teams usually are.

UnitThis gameUsual levelBetter or worse than usual
Falcons offenseEPA per play gained −0.08 +0.14 worse by 0.22
Falcons defenseEPA per play allowed +0.33 +0.16 worse by 0.17
Vikings offenseEPA per play gained +0.33 +0.09 better by 0.23
Vikings defenseEPA per play allowed −0.08 +0.06 better by 0.14

EPA (expected points added) per play on competitive snaps, turnovers left out because they are valued as luck. Usual level: the team’s earlier games this season plus half of last season, pulled toward the league average. One team’s defense and the other team’s offense are the same snaps, so one game can’t fully say whose day it was; it shows how far this one was from both teams’ norms.

How 4,000 replays ended

Falcons win 74% of them, Vikings 26%, counting the 4% still level after regulation as half each. The line is what actually happened: Vikings by 16.

Show as a table
Final margin in the replaysShare of replays
Falcons by 17+24.9%
Falcons by 9–1621.1%
Falcons by 1–825.1%
Level after regulation4.1%
Vikings by 1–814.2%
Vikings by 9–167.1%
Vikings by 17+3.4%

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 +0.7 points to the Vikings: the final margin was Vikings by 16, without the luck Vikings by 15.3. Luck shares are the fitted ones (how much of each kind is luck).

Penalties: Falcons 9 for 78 yards, Vikings 11 for 100 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
Q1 12:53 Offensive Holding on the Vikings (Kyle Rudolph), 10 yards, wiping out the play +5% ATL +2.3 pts
Q1 10:23 Neutral Zone Infraction on the Vikings (Everson Griffen), 5 yards · pre-snap +2% ATL +1.3 pts
Q1 7:03 Neutral Zone Infraction on the Vikings, 5 yards · pre-snap +1% ATL +1.4 pts
Q1 3:16 Illegal Block Above the Waist on the Falcons, 10 yards +1% MIN +0.9 pts
Q2 15:00 Illegal Block Above the Waist on the Vikings, 10 yards, wiping out the play +3% ATL +1.8 pts
Q2 10:44 Defensive Offside on the Vikings (Anthony Barr), 5 yards, wiping out the play · pre-snap +1% MIN +0.2 pts
Q2 8:23 Defensive Pass Interference on the Falcons (Isaiah Oliver), 15 yards +1% MIN +0.9 pts
Q2 7:28 Defensive Holding on the Falcons (De'Vondre Campbell), 5 yards +2% MIN +1.5 pts
Q2 4:40 Neutral Zone Infraction on the Falcons (Russell Gage), 5 yards · pre-snap 0% MIN 0.0 pts
Q2 2:00 Offensive Holding on the Falcons, 10 yards, wiping out the play +3% MIN +1.7 pts
Q3 8:11 Neutral Zone Infraction on the Vikings (Shamar Stephen), 5 yards · pre-snap +1% ATL +1.0 pts
Q3 3:55 Defensive Pass Interference on the Vikings (Trae Waynes), 26 yards +2% ATL +3.2 pts
Q3 1:15 Lowering the Head to Initiate Contact on the Falcons (Ricardo Allen), 15 yards 0% MIN +1.8 pts
Q3 0:53 Lowering the Head to Initiate Contact on the Falcons (Keanu Neal), 8 yards 0% MIN +1.1 pts
Q4 4:39 Kick Catch Interference on the Vikings (Kris Boyd), 15 yards 0% ATL +1.4 pts
Q4 4:39 Delay of Game on the Vikings, 5 yards · pre-snap 0% ATL +0.6 pts
Q4 4:28 False Start on the Falcons (Calvin Ridley), 5 yards · pre-snap 0% MIN +0.7 pts
Q4 3:04 Defensive Pass Interference on the Vikings (Kris Boyd), 9 yards 0% ATL +1.3 pts
Q4 2:29 Illegal Use of Hands on the Vikings (Stephen Weatherly), 5 yards, wiping out the play 0% ATL +2.0 pts
Q4 1:05 Illegal Touch Kick on the Falcons, 5 yards 0% MIN +0.5 pts

Falcons penalties, every game · Vikings penalties, every game · All teams, 2019

When it happened

Vikings’ chance of winning

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 Vikings were ahead in it, below while the Falcons were.
#WhenWhat happenedWin probability forNext drive
1 Q1 12:59 Blocked punt by the VikingsSpecial teams +11% MIN MIN: Touchdown
2 Q1 12:53 Offensive Holding on the Vikings (Kyle Rudolph), 10 yards, wiping out the playJudgment calls · no snap history yet +5% ATL ATL: Turnover
3 Q2 15:00 Illegal Block Above the Waist on the Vikings, 10 yards, wiping out the playJudgment calls +3% ATL ATL: Turnover
4 Q2 13:52 The Vikings fumbled and recovered it themselvesFumble bounces · loose balls are close to 50/50 +3% MIN MIN: Punt
5 Q2 10:26 The Falcons fumbled and the Vikings recoveredFumble bounces · loose balls are close to 50/50 +3% MIN ATL: Punt
6 Q2 9:00 The Vikings converted 3rd & 93rd & 4th downs · 31% expected +3% MIN MIN: Touchdown
7 Q2 7:28 Defensive Holding on the Falcons (De'Vondre Campbell), 5 yardsJudgment calls · no snap history yet +2% MIN MIN: Touchdown
8 Q2 2:00 Offensive Holding on the Falcons, 10 yards, wiping out the playJudgment calls +3% MIN MIN: Punt

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

Falcons 1% · Vikings 99%

Final margin
Vikings by 16
Luck in points
0.7 for the Vikings
Luck-adjusted margin
Vikings by 15.3
Replay with same day's form
Falcons 74% · Vikings 26% 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 1 2019 games · Falcons · Vikings

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