Example
A range from 100 to 110 has equilibrium at 105.
In practice
The concept is a filter on price. Buying in the lower half of a range means entering closer to the level that would prove the idea wrong, with more room to the target. Buying in the upper half means paying more for less.
Traders draw the range, find the midpoint and then only take long setups below it and short setups above it, however good a setup on the wrong side looks.
What to watch for
In a strong trend price may never pull back into discount, and waiting for it means missing the move. The reading also depends entirely on choosing the right range.