Standard Deviation (SDV)
SDV(Vector, Periods, Standard Deviations, MA Type)
Standard Deviation is a common statistical calculation that measures volatility. The SDV function computes the volatility the same way as the Bollinger Bands, which is a rolling average of the standard deviation.
Major highs and lows often accompany extreme volatility. High values of standard deviations indicate that the price or indicator is more volatile than usual.
Standard Deviations: 2
MA Type: SIMPLE
set SDV21 = SDV(CLOSE, 21, 2, SIMPLE)
set BUY = SDV21 > REF(SDV21, 10)
Evaluates to true when 21 period Standard Deviations are greater than 10 days ago.