Baseline Rate
The rate at which price moved a given way over a given period without any signal present. It is the comparison a signal's success rate has to beat to mean anything.
This is the single most important idea for reading any published win rate. In a market that rose on 60% of days, a bullish signal that "works 60% of the time" has found nothing — it has measured the market. Every success rate on this site is quoted against a time-matched baseline for exactly this reason.