Elliott Wave Theory
Elliott Wave Theory is a form of technical analysis developed by Ralph Nelson Elliott in the 1930s that describes recurring fractal patterns of five-wave impulse sequences and three-wave corrective sequences in historical price data, based on the idea that market prices reflect collective investor psychology that moves in identifiable patterns.
Ralph Nelson Elliott developed his wave theory in the 1930s after observing the historical price charts of the Dow Jones Industrial Average. Elliott identified what he believed to be a repeating structural pattern in equity price history: markets move in five waves in the direction of the dominant trend (three impulsive waves advancing and two corrective waves between them), followed by a three-wave correction (labeled A-B-C) against the prior trend. He further observed that this five-three structure appeared to repeat at different time scales simultaneously — a property now described as fractal or self-similar.
Elliott drew on the Fibonacci number sequence to describe the proportional relationships he observed between waves in the historical record. Ratios derived from Fibonacci numbers — such as 0.618, 0.382, and 1.618 — have been referenced by Elliott Wave practitioners as historically occurring levels of wave retracement and extension in U.S. equity price data. The application of Fibonacci ratios within Elliott Wave analysis became more systematized through the work of A.J. Frost and Robert Prechter, whose 1978 book on the theory brought it to wider attention in the U.S. financial community.
Elliott Wave Theory remains one of the most discussed and debated frameworks in the technical analysis literature. Its practitioners argue that the wave structure reflects observable psychological crowd patterns in market history; its critics argue that the rules governing wave identification are sufficiently subjective that analysts can draw contradictory wave counts from the same price chart. Academic research on the predictive validity of Elliott Wave analysis has produced mixed results, with studies noting the difficulty of standardizing wave identification across analysts.
As with all technical analysis frameworks, Elliott Wave Theory represents an attempt to describe historical price patterns. Its historical observations about price structure in U.S. equity markets do not constitute a reliable method of forecasting future prices, and no investment or trading decision should be made solely on the basis of any Elliott Wave interpretation.
The degree hierarchy within Elliott Wave Theory — in which grand supercycles contain supercycles, which contain cycles, which contain primary waves, and so on through intermediate, minor, minute, and minuette degrees — reflects the fractal self-similarity that Elliott observed in historical chart data across different time spans. Analysts applying the framework to U.S. equity index history have mapped wave counts over spans ranging from decades to intraday minutes, with different practitioners arriving at different counts depending on the data resolution and subjective wave-labeling rules applied. This inherent ambiguity in wave identification is widely acknowledged in both academic and practitioner discussions of the framework.