Force Index oscillator was developed by Alexander Elder. Its main function is to measure bullish forces during each upward movement and bearish forces during each downward movement.
The force of each market movement is defined by its trend, range and volume:
Force Index formula:
RAW FORCE INDEX = VOLUME (i) * (CLOSE (i) - CLOSE (i - 1))
FORCE INDEX = MA (RAW FORCE INDEX, N)
Where:
Smoothing by a short moving average (2 period) helps to find favourable moments to open and close positions. If smoothing is made by a long moving period (e.g. 13-period) the Force Index oscillator reveals if the trend has changed or not.
The main Force Index oscillator signal is a bullish divergence / bearish convergence:
Force Index