In the case of a head and shoulders top the leg support can send the price back above the neckline, cancelling the pattern. The same phenomenon can be found in reverse head and shoulders patterns and double tops and bottoms. A target measured by expressing the measurement distance as a percentage and applying that percentage to the point of breakout. The measurement distance is applied to the point of breakout from a geometric pattern to give a target. A support or resistance line that forms the boundary of a top or bottom pattern such as double top or double bottom, or head and shoulders top or reverse head and shoulders.
Breakout occurs when the price of a stock or level of an index passes the neckline.
Measurement of a target is taken from the neckline at the point of breakout. The measurement distance is taken from the neckline to the most distant vertical point in the geometric pattern. In essence, a geometric pattern gives rise to the presumption that at least one half of a trend has occurred, allowing the trader to take advantage of the other half of the market move and giving hope that the trend will continue further by reason of a chain of patterns. The geometric patterns comprise the head and shoulders top, reverse head and shoulders, double top, triple top, double bottom triple bottom, triangles, pennants and wedges. The pennant should be preceded by an almost vertical market move, called the pole.