The Alternate Signal To Noise Ratio was created by John Ehlers (Rocket Science For Traders pgs 84-85) and this is a variation of his signal to noise ratio that some scalpers might find more useful than his default signal to noise ratio. You would want to buy and sell when the indicator is above the dotted line because that means the stock is volatile enough to maximize any movement of the trade in either direction. Buy when the indicator line is green and sell when it is red.
Let me know if there are other indicators you would like to see me publish or if you want something custom done!