This strategy will enter into long position based on the volatility of prices implied by indicators of (a) Bollinger bands, and (b) ATR.
Application of Bollinger bands ("BOLL")
Using plain vanilla settings for BOLL (i.e. 20 period moving average, and 2 standard deviations of closing prices), we are interested to know about the shape of the area that is bounded by the upper and lower bands.
In theory, consolidation happens when volatility of price decreases. Visually speaking, this is represented by the narrowing of the upper/lower bands. This strategy considers the narrowing of BOLL bands as the primary indicator for long-entry.
Application of ATRs (as confirmations)
Firstly, to confirm that BOLL bands are narrowing (as mentioned above), the ATR at a potential point of entry is compared against the standard deviation of prices over BOLL's lookback periods. Once again, visualizing the shape of BOLL bands during consolidation, we assume the lines begin to squeeze when the distance between the center line and upper/lower band is less than two current ATRs.
Secondly, this strategy looks into the moving average of ATRs to assure that prices are not too choppy when entering into market. If the moving average of ATR decreases at a point in time such that all the above conditions are met, then we can assert that the volatility of price is decreasing.
Thirdly, ATR is used for determining the size of our trailing stop loss. We will keep the multiplier fixed at two.