Immediate definition
In plain words — The chapters show the method; the appendices collect the data, formulae, and procedures Hurst used to support it. They are six distinct doors, not one single “scientific proof.”
Appendices I–VI are the most technical portion of The Profit Magic of Stock
Transaction Timing. This page is a reading map: it explains the question
addressed by each section and where to continue. Claims remain attributed to
the 1970 book; source-checked does not mean independent replication.
I–II: spectrum and commonality
Appendix I presents an analysis of the Dow from 1921 to 1965. Hurst describes a line spectrum, “comb” filters, and an inverse relation between amplitude and frequency written as a = k/ω. This is the empirical core of the book's claim of cyclic order. Its dedicated entry also records the discrepancy between the printed 2,229 points and the roughly 2,300 cited in Chapter 11.
Appendix II extends the argument to individual securities by comparing the Dow and S&P 500 during 1949–1961. Hurst reads the similarity of their fluctuations as shared commonality. The comparison is part of his historical argument, not a modern estimate of how many securities retain that structure.
III: interval and return
Appendix III relates mean transaction duration and return over a sample of 300 stocks, identifying a “knee” around 10–20 weeks. This section supports the book's preference for short intervals and reinvested capital. Compounding and annualisation, however, require strong assumptions: opportunities, costs, capacity, and risk do not necessarily remain constant.
IV–VI: tools
Appendix IV derives the response of a centred moving average: half-span lag, a zero when period equals span, and response lobes. It shows that an average is a filter with attenuation and distortion, not a neutral line.
Appendix V uses parabolic interpolation to move outputs calculated at different spacings onto a common grid. Appendix VI describes Prony's method for estimating frequencies, amplitudes, and phases through trigonometric fitting. In both cases, close fit to observed data does not guarantee that parameters and components remain stable in the future.
A useful reading order
A beginner may start with III, which explains the interval philosophy, and then IV to understand moving averages. A technical reader may follow I → II → IV → V → VI while separating data, assumptions, and mathematical transformations at each step. Formulae specify the calculation; they do not automatically convert a market hypothesis into predictive evidence.
A serious verification would require original data, complete parameters, reproducible code, and out-of-sample evaluation. The appendices document Hurst's research programme and apparatus; they do not settle contemporary effectiveness by themselves.
Sources
- J. M. Hurst, The Profit Magic of Stock Transaction Timing, Prentice-Hall, 1970, Appendices I–VI, pp. 187–216 — primary source for the full apparatus.
- Campbell R. Harvey, Yan Liu, and Heqing Zhu, … and the Cross-Section of Expected Returns, NBER Working Paper 20592, 2014 — modern multiple-testing criteria; it does not replicate Hurst's appendices.