Algorithmic Trading can be a complex subject. Keep your knowledge current with this glossary of key concepts, terminology, and technical indicators.
The difference in price from the midpoint of a trough to the midpoint of a peak of a security. Amplitude is positive when calculating a bullish retracement (when calculating from trough to peak) and negative when calculating a bearish retracement (when calculating from peak to trough).
Chart pattern analysis says that after a retracement, price will continue to move at least a distance equal to the retracement's amplitude.