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Football Stat Definitions

Glossary of all football statistics used across the site

Football > Definitions

All stat categories, model concepts, and definitions used across Football pages.

Panna Model

The Panna rating system is a predictive player value model for association football, analogous to TORP for AFL.

Term	Description
Panna	The headline career-trait rating: a recency-weighted, multi-season adjusted plus-minus (xG/90). “How good is this player” — the best guess of their next-match impact. Offense − Defense; higher = more valuable.
Piero	A composite player rating — one number blending the three trait ratings Panna, EPR and PSR (panna-led, 0.5 / 0.3 / 0.2), z-scored across the pool and rescaled onto the Panna (xG/90) scale. The player-level cousin of the team Tiento; named after Alessandro Del Piero.
xRAPM	The per-season version of the same impact metric — this season’s adjusted plus-minus contribution. Panna is the career-weighted version of it (xRAPM is the building block).
Offense	Offensive component of Panna — expected goals (xG) created per 90, adjusted for teammate and opponent quality.
Defense	Defensive component of Panna — xG prevented per 90. Negative values are better (more xG prevented).
SPM	Statistical Performance Metric — box-score regularized plus-minus, the prior xRAPM/Panna shrink toward.
Percentile	Player’s rank as a percentile among all rated players (100 = top).

World Cup 2026

Term	Description
Tiento	The headline national-team strength rating for the World Cup: goals better (or worse) than the average qualified side on a neutral pitch. A blend of four independent systems — squad Panna (35%), EPR (25%), Elo (25%), PSR (15%) — z-scored and calibrated against the match model’s own fixture predictions. Named for the ball Argentina supplied for the first half of the first-ever World Cup final (Montevideo, 1930). Drives the Simulator’s knockout ties.
BT	Bradley-Terry tournament strength — the match model’s predictions for all 1,128 possible team pairings compressed into one number per team. Host advantage (USA, Canada, Mexico) is baked in, so it reads as expected strength at this tournament.
EPR (squad)	Squad aggregate of player Expected Possession Ratings — per-90 expected possession value summed across the squad’s projected contributors.
PSR (squad)	Squad aggregate of player box-score skill ratings.
Champ %	Probability of winning the tournament, from the 10,000-run Monte Carlo simulation.

Possession Value & Win Probability

Per-match value breakdowns, live on the match and match events pages:

Term	Description
EPV	Expected Possession Value — the probability the team in possession scores next, given the current game state.
EPV credit / Equity	Per-action credit assigned to each player based on how their action moved EPV. Positive = value added, negative = value lost. Summed per player per match on the events pages.
WPA	Win Probability Added — per-action change in the team’s chance of winning, credited to the actor (and receiver where relevant).
EPR	Expected Possession Rating — a player’s predictive rating derived from historical EPV contributions, per 90.
PSR	Performance Skill Rating — predictive rating built from box-score skill estimates.

Box-Score Stats

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