Floor-Ceiling Spread
The gap between your worst and best finish. A spread of 2 is a metronome; a spread of 7 is a wild card.
worst_placement - best_placement (lower is better)
Best at
A quick volatility check that needs no explaining.
Where it misleads
Looks only at the two extremes, so one freak result reads the same as constant swinging, and ties are everywhere.
How it works
Floor-Ceiling Spread measures the gap between your worst and best finish. A player who ranges from 1st to 8th has a spread of 7; one who's always 2nd-4th has a spread of 2.
How it works: Spread = worst_placement - best_placement. Lower spreads rank higher. A spread of 0 means perfectly consistent (always the same finish position).
When to use it: As a quick volatility check. It's simpler than full variance calculation and immediately tells you whether a player is a wild card or a steady performer. The result label is already "Spread" because that is what the method actually outputs.
Watch out for: Only looks at the two extremes, ignoring everything in between, so it creates heavy ties and can overreact to one unusually good or bad match. A player with 20 matches and placements of [1, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 8] has the same spread as one who constantly bounces between 1st and 8th.