📐 Open Science & Reproducibility
Scoring Methodology
How Footbillion calculates rarity valuations deterministically using open-source historical records.
Open-Access Data Sources
Footbillion is built exclusively from verified open datasets: Fjelstul World Cup Database (CC BY-SA 4.0) and OpenFootball football.json (CC0). No scraping or proprietary closed APIs are used.
Valuation Algorithm
Within each prompt, candidate entities are sorted by a multi-factor historical prominence score (appearances, goals, awards, and finishes). The list is then linearly mapped to fixed £10m to £150m valuations in 5-point increments.