James Marsden Hurst 1924—2005

Chapter 12.1

The Appendices — The Profit Magic (1970)

The book's six appendices: the method's scientific foundation — the line spectrum, commonality generalized, the transaction interval, the averages' response, parabola and Prony.

On this page

Who this entry is for — The chapters teach the craft; the appendices show why it is legitimate. This is the part of the book written for those who want the proofs: six technical dossiers, from the great 44-year spectrum to curve fitting. This is the annotated index.

Source: J. M. Hurst, The Profit Magic of Stock Transaction Timing, Prentice-Hall, 1970 — Appendices I–VI (pp. 187–216).


The six appendices

# Title In one line Entry
I The Not-to-Be-Expected "Order" The 1921–1965 spectrum: line structure, the a = k/ω law, the comb filters The DJIA spectrum, 44 years
II Extension to Individual Issues Dow ≡ S&P 500 to the finest detail → the signature holds for ≥¼ of issues Commonality generalized
III Transaction Interval Effects 300 stocks: the 10–20 week "knee" and compounding's role The transaction interval
IV Response of a Centered MA aᵣ = (1+2f)/n: half-span lag, zero at the span, constant −0.23 lobe How a moving average responds
V Parabolic Interpolation One parabola per triple: filters at different spacings on a common grid Parabolic interpolation
VI Trigonometric Curve Fitting Prony: frequency, amplitude and phase measured objectively Trigonometric curve fitting

How to read them

In plain words — Two appendices are theses (I and II: the order exists, and holds for most of the list), one is a motive (III: why shorten the interval), three are tools (IV, V, VI: the kit for anyone who wants to redo the maths).

The natural path: first Appendix I — which holds the book's deepest result, the equality of every cycle's maximum rate of change (the state table's justification) — then Appendix II, which generalizes it. Appendix III you have already met in Ch. 1: it is the arithmetic foundation of the operating philosophy. The last three accompany Ch. 11: IV explains the tool you use every day, V and VI close the spectral-research pipeline.