Boll index is one of the commonly used tools for technical analysis of stock market. By calculating the "standard deviation" of stock price, we can find the "trust interval" of stock price. Like MACD, RSI, KDJ and other indicators, BOLL indicator is also the most practical technical analysis reference indicator in the stock market.
The bollinger Band consists of four lines, which are divided into B 1 line, B2 line, B3 line and B4 line. The line B 1 is the exponential (or stock price) resistance line, and the line B4 is the support line. From the width of the bollinger band, we can see the fluctuation range of the index or stock price. When the stock price is consolidating, the four lines contract, which is called convergence. When the stock price breaks up or down, the four lines open, which is called opening positions.
When the stock price breaks through the resistance line B 1 upwards, the selling point appears, and when it breaks through the B4 line downwards, the buying point appears. When the stock price rises (falls) along the resistance line (support line), although it has not broken through the support line (pressure line), it has already broken through the B2 line (B3 line), which is also a good selling (buying) point.
Extended data:
Among all the index calculations, the calculation method of BOLL index is the most complicated one, in which the concept of standard deviation in statistics is introduced, which involves the calculation of middle track (MB), upper track (UP) and lower track (DN).
In addition, like other indicators, BOLL indicators include daily BOLL indicators, weekly BOLL indicators, monthly BOLL indicators, annual BOLL indicators and minute BOLL indicators.
Daily BOLL index and weekly BOLL index are often used in stock market research. Although their calculated values are different, the basic calculation method is the same. Take the daily BOLL index calculation as an example, and the calculation method is as follows:
The calculation formula of daily BOLL index: middle track =N daily moving average; Upper trajectory = middle trajectory+double standard deviation; Lower trajectory = middle trajectory-double standard deviation
Calculation process of daily bell index
1) Calculate the sum of closing prices in Ma: Ma = n days ÷N
2) calculate the standard deviation MD:
MD= the sum of two powers of square root n days (C-MA) divided by N3) Calculate MB, UP and DN lines.
Mb = mobile authorization on the (n- 1) th day.
Up =MB+2×MD
DN=MB-2×MD
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