indicator Force Index
strength indicator is interesting, perhaps, only that was developed by Alexander Elder.
Measures "strength" of the bulls at each increase, and the "strength" of bears in each recession. Typically, the index shall be rounded off by a moving average.
classical description of the following:
Better to buy when in an uptrend strength indicator will be minus (fall below the zero line);
Climbing to new heights, signal strength indicator on the continuation of the uptrend;
The signal to sell comes when, during a downward trend strength indicator becomes positive;
Falling on a new depth, strength indicator indicates the strength of the bears and the continuation of the downward trend;
If price changes are not backed by corresponding changes in volume, the power indicator is on one level, which tells you the trend is going.