TRANSPARENCY IS PART OF THE MODEL
Inside the hockey lab.
What ICECAST knows, what it models, and what still needs to be proven.
Real data. One snapshot.
Current standings, team summary statistics, active rosters, and club statistics come from NHL APIs. A simulation batch uses one immutable snapshot. A failed source produces an error, or clearly marked cached data for up to 24 hours; statistics are never fabricated.
A game, built event by event.
The seeded model advances in six-second steps through neutral ice, zone entries and offensive possessions. Passes, turnovers, shot attempts, blocks, misses, saves, rebounds and goals alter the next state. Only shots on goal can score or create saves.
Tendencies, with uncertainty.
Current-season team rates are blended with the previous season using a 20-game prior. Shot generation combines attacking volume and opposing suppression. Player shooting shares and finishing are shrunk using pseudo observations. Goalies use a 500-shot prior at .905 save percentage. These are explicit modeling assumptions, not fitted estimates.
Shot quality, not official xG.
ICECAST heuristic xG uses generated distance, angle, rebound context, strength, shooter and goalie effects. The base equation is 0.19 × exp(−distance / 57) × (1 − 0.55 × |angle| / 90), with a 1.55 rebound multiplier. Coordinates are generated; the coefficients have not been fitted to historical NHL events.
Rules and known simplifications.
Regulation has three 20-minute periods. Regular-season overtime is five minutes, three on three, with sudden death and then a three-round shootout plus paired sudden death. Playoffs use repeated 20-minute sudden-death periods. Minor penalties last two minutes and end on an opposing power-play goal. The model allows one minor per side; majors, delayed penalties, double minors, icing and offsides are not modeled.
A replay, generated by ICECAST.
The viewer interpolates role-based formations from the event sequence. It is an illustration of the simulated game, not recovered tracking footage. Five skaters and a goalie appear at even strength, with adjusted numbers for penalties, overtime and late-game goalie pulls. Player shifts use simplified rotating lines.
EDGE without invented precision.
NHL EDGE is displayed separately with season, source, units, and retrieval time. Public summaries expose skating speed, distance, shot locations and zone time, but not raw positional trajectories. EDGE is not yet included in the predictive model; its value must be tested first.
Validation status: experimental.
Reproducibility and event invariants are tested. No historical accuracy, Brier score, log loss, calibration improvement or betting edge is claimed. Historical backtesting must use archived pregame snapshots to prevent information leakage. Monte Carlo confidence intervals describe simulation sampling error only.
Source references
NHL Web API · standings NHL Stats API · team summaries NHL EDGE · public tracking summariesICECAST is an independent research application and is not affiliated with or endorsed by the NHL.