Indicators
Simple statistics traders use: how far a market usually moves in a day, how unusual a move is, and how markets move together.
Average daily range (ADR) is the average of the daily high minus low over the last few days (5, 14 and 20 are common). If a market has already moved its full ADR today, a further big move is less likely, though not impossible. Standard deviation measures how spread out prices or returns are; a z-score says how many standard deviations a value is from its average, a rough way to call a move unusual.
The correlation coefficient runs from −1 to +1 and measures how two markets' returns move together. EURUSD and GBPUSD are usually strongly positive; EURUSD and the dollar index strongly negative. For prop accounts it matters because two positions in highly correlated markets are close to one bigger position.
For education only, not financial advice.