Return value of the Lower Bollinger band technical indicator.
Syntax:
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BollingerDown[N](price) |
Calculation :
Bollinger bands are enveloppes based on a moving average and a standard deviation.
This standard deviation makes bands widen or narrow, according to market volatility. The first parameter is the number of days for the moving average. Second parameter is the standard deviation.
Interpretation :
95% of the price must be inside the bands if one can presume that prices follow a normal gaussian distribution (bell curve). The bands thus constitute strong zones of support and resistance when the market is without clear trend (ranging). When the difference between the two enveloppes drops after having increased, the trend loss its force.
Example:
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//last bar piercing the lower Bollinger Bands bollD = BollingerDown[20](close) if(Open[1]>bollD[1] AND Close[1]<bollD[1]) THEN VAR = 1 ELSE VAR = 0 ENDIF RETURN VAR as "LOWER PIERCING SIGNAL" |