Skip to content
CyclepediaThe trading encyclopedia
SESSION
ITENESPT-BRFRDE
James Marsden Hurst 1924—2005 Biography and works
Chapter 3.3 — Verify Your Chart Patterns

Head and shoulders in Hurst's cyclic model

Hurst reconstructs head and shoulders by adding a short wave to a slower component that is turning; it is a historical explanation of the shape, not automatic proof of its cause.

Cite this entry

This reference cites the Cyclepedia entry. The documents it draws on are listed in the entry’s sources.

On this page

In one sentence — A short wave keeps rising and falling while a slower component reaches its high and turns: the three resulting peaks can look like a shoulder, a head, and a shoulder.

The shape without the jargon

Imagine three consecutive short waves. If the slow background is still rising beneath the first, near its high beneath the second, and already falling beneath the third, the middle peak will stand above the other two. The pattern need not be drawn afterwards: in Hurst’s construction it emerges from the sum of the components.

One possible shape when the slow background turns Interactive figure with left shoulder, head, right shoulder, neckline, and interpretation limit. Two rhythms, one shape Teaching reconstruction of Hurst’s proposed explanation shoulder head shoulder neckline The shape is compatible with the model · it is not exclusive proof Cyclepedia diagram · Emiciclo
A teaching reconstruction of the model: the slow background rises, tops, and falls while the short wave continues to oscillate. Tap the four points to follow the logic.
Select the highlighted points to explore the detail

Hurst's historical example

In Chapter 3 of The Profit Magic of Stock Transaction Timing, Hurst combines components on the order of 18 weeks and 18 months with a linear background. He uses them as an illustrative example; he is not saying that every market head and shoulders must have exactly those durations.

The short component creates the nearby peaks. The long component first raises and then lowers their level. The sum also displays trend lines, channels, and breaks resembling those already used by chartists. The historical point is specific: shapes treated as separate patterns can be compatible with a single composite-motion model.

Why does a neckline appear?

The first rising trend line joins two lows. After the slower component has topped, the next low forms lower. Joining the last two lows produces a second line with a smaller or negative slope: the neckline.

In the model this line does not exert a force on price. It is a geometric description of the lows made by the sum. Its break says that the previous slope no longer describes those points; by itself it does not establish how long the following move will last.

The same family under different phases

When the components reach their highs under a different phase relationship, the middle crest may not dominate: a double top or a more or less symmetric V can appear. Turning the construction upside down produces an inverse head and shoulders or a double bottom.

This is useful because it shifts the question from “what is the drawing called?” to “which oscillations and timescales might produce it?”. Visual similarity, however, does not uniquely identify the components: different combinations can create similar shapes.

What can we conclude today?

Hurst offers a generative explanation: he shows how the pattern can arise inside his model. He does not prove that every observed head and shoulders has a cyclic origin, or that its break is automatically profitable.

Modern research has made selected patterns measurable through algorithmic procedures. Lo, Mamaysky, and Wang find that some shapes contain incremental information in certain samples. Savin, Weller, and Zvingelis examine head and shoulders and subsequent returns specifically: they report predictive power under some conditions, but little support for the profitability of the pattern when used on its own. These empirical results are separate from Hurst’s historical construction, not a validation of it.

Evidence boundary — A head and shoulders is compatible with Hurst’s proposed sum. It is not exclusive proof of the cause, does not establish targets, probabilities, or economic value by itself, and must be defined before it can be tested.

Sources

Suggest an edit My proposals