股票
Bollinger Bands - traditional general approach
Bollinger bands are very similar to moving averages. The bands are plotted at two standard deviations above or below the moving average. This is typically based off of the simple moving average, but an exponential moving average can be used to increase the sensitivity of the indicator. A 20-day simple moving average is recommended for the center band and 2 standard deviations for the outer bands. Bollinger bands are typically used by traders to detect extreme unsustainable price moves, capture changes in trend, identify support/resistance levels and spot contractions/expansions in volatility. There are a number of ways to interpret Bollinger Bands: when the prices break above or below the upper or lower band, it is an indication that a breakout/breakdown is occurring. Alternatively, some traders use Bollinger Bands as an overbought and oversold indicator. 0