Glossary
- Expected Points (EP): using scoring event probabilities, the estimated expected points with respect to the possessing team before the play; simply put, the value of a particular situation to the offensive team, measured by points (more here if you're curious)
- Expected Points Added (EPA): expected points after the play minus expected points before
- Completion Percentage Over Expected (CPOE): 1 - completion probability
- Completion Probability: probability of a completed pass based on comparable game situations
- Success Rate: percent of plays with positive EPA
- Yards Gained: yards gained (or lost) by the possessing team, excluding yards gained via fumble recoveries and laterals
- Yard Line: number of yards from line of scrimmage to offensive end zone
- Dropback Probability: probability of a dropback scaled from 0 to 1
- Air Yards: distance in yards perpendicular to the line of scrimmage at where the targeted receiver either caught or didn’t catch the ball
- Yards After Catch (YAC): distance in yards perpendicular to the yard line where the receiver made the reception to where the play ended.
- Kick Distance: distance in yards for kickoffs, field goals, and punts
- Completed Air EPA: EPA from the air yards alone on a completed pass (0 otherwise)
- Air EPA: hypothetical EPA from the air yards alone on a completed pass, regardless of whether it was completed
- Completed YAC EPA: EPA from the yards after catch alone on a completed pass (0 otherwise)
- YAC EPA: EPA from the yards after catch alone on completion, difference between hypothetical air EPA and raw observed EPA on incompletion
- Win Probability (WP): estimated win probabiity for the possessing team given the current situation at the start of the play
- Win Probability Added (WPA): win probability after the play minus win probability before
- Completed Air WPA: WPA from the air yards alone on a completed pass (0 otherwise)
- Completed YAC WPA: WPA from the yards after catch alone on a completed pass (0 otherwise)
- Vegas Total: closing Vegas line for the game (via Pro-Football-Ref)
- Mean Expected YAC: average expected yards after the catch based on where the ball was caught
- Expected YAC EPA: Expected value of EPA gained after the catch, starting from where the catch was made; zero yards after the catch would be listed as zero EPA
- QB EPA: gives QB credit for EPA for up to the point where a receiver lost a fumble after a completed catch; makes EPA work more like passing yards on plays with fumbles