Colin Willan

Formula: Rating = 1000 + (weighted score × 400). Each factor is normalized to −1…+1, multiplied by its weight, then summed. Window: factors are computed from the Handicap Calculation Years only (2022, 2023, 2024, 2025, 2026), excluding walkovers — the same window the official recalculation uses. Bayesian shrinkage: the raw rating is pulled toward 1000 by confidence (window matches ÷ 33, an adaptive threshold set by the last recalculation). Offsets: division and B/C/D team offsets are then applied, weighted by where each window match was played. Recency blend: the calculation years are re-weighted at up to 40% by match volume. Players with a long career but fewer than 5 window matches fall back to their full career record. Rating maps to handicap 0–15 (lower = stronger) via the league's spread multiplier.