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Model Card

Two-parameter player RAPM variant with offense and defense estimated together. This is the first explicit expansion beyond a single player eta.

Each player's rating starts from a share of the player's previous-season RAPM rather than zero (NBA 50%, NCAAM 50%, NCAAW 50%; other leagues start from zero), so a few games move it less. The offense/defense split still starts from zero.

Validation here is out of sample. From two weeks into each season, every week's lineups are predicted by a fit on the season's earlier play, with the served settings; each player's point is the predicted and actual margin per 100 possessions of the held-out play the player was on the floor for.

Selected League / Season

Change league with the League selector at the top of the page.

Held-out player predictions

Plot RAPM Off/Def against any counting stat (one point per player; choose any season with a served list).

Not enough held-out play to show a validation plot. NCAAM 2026-2027: 0 eligible players. A player needs at least 200 held-out possessions. Held-out windows: 0. Held-out possessions: 0.0. Computed 2026-11-14 13:20:53.035023+00:00.

NCAAM 2025-2026: 3791 players with at least 200 held-out possessions. Across players, predicted and actual correlate at r = 0.84 (weighted by held-out possessions). Across these player averages, weighted R² = 0.69 (relative to the weighted mean of actual held-out outcomes). Per held-out segment, squared error is 1.1% below predicting the league average. Each dot is a player (500 with the most held-out possessions are plotted; larger dots had more); on the dashed line, actual equals predicted. Select a dot for the player.

Held-out miss against playing time

Each dot is a player's actual minus predicted margin per 100 possessions with the player on the floor against their held-out possessions (log scale). Orange points are the possessions-weighted mean miss of eight equal groups of players by playing time: a model that shrinks its low-possessions players too far, or not far enough, shows a slope.

Output Coverage

Rows in each model's current published run (or legacy rows where no run is selected).