Grand Canyon Baseball
Defense App
Outs Above Average from TrackMan fielder positioning
Model primer
Every ball in play has an expected out probability.
OAA credits a fielder with 1 − expected out probability when they convert an out and debits the expected probability when they don't. Air balls use a catch probability model (distance to the landing spot, hang time, route direction); ground balls use an out-conversion model (distance to the ball path, exit velocity, spray angle). Models are trained on the full 2025 college season and scored on 2026.
Alternate OAA lens
WAR-style shortstop method
The referenced shortstop notebook builds the same OAA ledger from a different feature set: estimate out probability from the fielder's starting spot, batted-ball location, movement speed, hang time, launch metrics, and a throw/handling-time estimate. The scoring is unchanged: made play = 1 − xOut; missed play = −xOut.
Purple = lower percentile · white = midpoint · gold = higher percentile. Click a player for the position breakdown and their biggest plays. Sorted by OAA; click headers to re-sort.
Sum of player OAA on chances while the team was in the field.
DRS = rPM + rGDP + rSB, in runs saved vs the level average. rPM converts outs above average to runs using run values from this season's own run-expectancy (RE24) deltas by position and batted-ball type. rGDP is double plays turned vs expected on fielded ground balls with a runner on first and fewer than two outs. rSB is the run impact of tagged stolen-base attempts (success vs caught) against the level-average attempt; steal tagging is sparse in TrackMan, so teams with no tagged attempts sit at 0. Base-out states are reconstructed from TrackMan pitch sequences.