ryurko / nflscrapR-data

Data files (.csv) accessed with nflscrapR and summarized at the player-level
https://ryurko.github.io/nflscrapR-data/
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Issue: Play-by-Play EPA data for Kick-Off Fumble Returns for TD is wrong #10

Open Bopper-CoH opened 6 years ago

Bopper-CoH commented 6 years ago

EPA is defined as the expected points added for the Possession Team (PT). On Kickoffs, the team receiving the kick is the PT.

However, on Kickoffs, if the KR team fumbles the ball and the Defensive Team (Kickoff Team) returns it for a TD, the EPA is positive. It should be negative since the Defensive Team scored.

There are 3 examples from 2013 play by play data. Below are details of one of these examples: GameID: 2013101303 TimeSecs: 1362 EPA: 6.54564648081907 Desc: G.Zuerlein kicks 70 yards from STL 35 to HOU -5. K.Martin to HOU 10 for 15 yards (R.McLeod). FUMBLES (R.McLeod), RECOVERED by STL-D.Bates at HOU 11. D.Bates for 11 yards, TOUCHDOWN.

Bopper-CoH commented 6 years ago

This problem might exist for all Turnovers on kickoffs. I'm seeing issues on plays that don't result in a fumble return for TD. GameID: 2016121112 TimeSecs: 3600 ExpPts: 0.814998476 EPA: 5.20788435782636 Desc: M.Bosher kicks 69 yards from ATL 35 to LA -4. M.Thomas MUFFS catch, touched at LA -4, RECOVERED by ATL-P.Worrilow at LA 3.