Ultimate Oscillator   

The Ultimate Oscillator compares prices with three oscillators, using three different periods for calculations.
Oscillators typically compare a instrument’s smoothed price with its price x-periods ago. Larry Williams developed the Ultimate Oscillator that uses weighted sums of three oscillators, each of which uses a different time period. Values range from 0 to 100 with 50 as the centerline. The overbought level is considered above 70, and oversold – below 30.
The timeframe and number of periods used in plotting Ultimate Oscillator can vary according to desired sensitivity and the characteristics of the instrument. Typically values of 7-periods, 14- periods and 28-periods are used. Note that these time periods all overlap, i.e. the 28-period time frame includes both the 14-period time frame and the 7-period time frame. This means that the action of the shortest time frame is included in the calculation three times and has a magnified impact on the results.