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1994issue C051-11

Market life expectancy as a risk filter

A classified trend can be turned into historical extent and duration odds, then used to cap how much of the book may stay long before a trade is placed.

  • A usable Risk-reward ratio starts with whether and how far to be long, using trend direction plus the odds that the current move continues versus reverses.
  • Dow Theory classifies the primary trend, secondary reaction, and daily fluctuation so each swing's extent and duration can be measured.
  • Classified historical swings form frequency distributions of extent and duration, so a live move can be treated as having a remaining life expectancy.
  • Life-expectancy tables are a foundation for keeping odds, then weighted with other checks so an aged move is not squeezed late.
Entries in this reading3 entries
Expected value18 readingsRisk-reward ratio19 readingsCurrent trackDow Theory29 readings

Start with how far to stay long

A usable Risk-reward ratio starts with whether and how far to be long, using trend direction plus the odds that the current move continues versus reverses.

Quantified entry and exit rules, independent of later rationalization, are built after the economic backdrop and the market's place in that backdrop are stated.

Classify the swing before measuring it

Dow Theory's three concurrent movements, the primary trend, the secondary reaction, and daily fluctuation, supply the classification used to measure each swing's extent and duration.

Classified historical swings show statistically usable frequency distributions of extent and duration, so a live move can be treated as having a remaining life expectancy.

A median-age book cap

As of the February 1992 snapshot, an 18-index average upswing of 18.6% over 74.4 days sat near median life: 53.5% of like swings were larger and 67.3% lasted longer, implying roughly a 40% chance the move would end soon and a suggested long cap near 60% of maximum stock exposure if that statistic were used alone.

When segment profiles invert the cap

Segment profiles can invert the same filter. OTC industrials at 41.7% over 215 days were in a thin historical tail, with only 14.2% of comparable swings larger and 26.5% longer, while the DJIA at 14.4% over 60 days still had most comparable swings larger and longer.

Exposure through an intermediate swing

The same age filter is meant to raise and cut exposure across an intermediate swing: fuller long early, lighter before a secondary reaction, flat or short in the reaction, then long again near its low.

Primary upswings that sat well past median extent and duration preceded several historical breaks, including 29.9% in 99 days before 29 October 1929, 26.9% in 96 days before Black Monday, and 24.4% in 200 days in October 1989.

Bull-market secondary correction extents, 1896–1991

Each point is one historical secondary correction, ranked from the smallest retracement of the prior primary swing to the largest. Industrials and transports move together: most corrections sit between about 25 and 75 percent, then a thin tail runs past a full retracement. A live correction can be read against this curve to see how much of the historical sample is already behind the market. Figures come from Sperandeo’s Figure 1 table for the DJIA and DJTA through February 1991, not from the qualitative quartile sketch.
Each point is one historical secondary correction, ranked from the smallest retracement of the prior primary swing to the largest. Industrials and transports move together: most corrections sit between about 25 and 75 percent, then a thin tail runs past a full retracement. A live correction can be read against this curve to see how much of the historical sample is already behind the market. Figures come from Sperandeo’s Figure 1 table for the DJIA and DJTA through February 1991, not from the qualitative quartile sketch.DJIA and DJTA · 1896 to February 1991 · 1896-01-01T00:00:00.000Z to 1991-02-28T00:00:00.000Z

Sample is bull-market secondary corrections only, classified on the DJIA and DJTA. Sperandeo notes that 95 percent last more than 14 calendar days and 98 percent retrace at least 20 percent of the previous primary swing. Rows are sorted by size, not by date. A few OCR gaps in the print (18 0, 46 0, 41 3, l13.7, 120.l) were read as 18.0, 46.0, 41.3, 113.7 and 120.1 to keep the ranked sequence intact.

Keep the odds, then weight them

Life-expectancy tables are a foundation for keeping odds, not a guarantee. Remaining probabilities are then weighted with other fundamental and technical checks so late-stage squeezing of an aged move is avoided.

Editorial: Expected value is the later bound on that weighted remainder, so the table stays an exposure filter rather than a stand-alone call to stay long.

Educational research material, not investment advice. Historical source context does not establish present-day performance.
10 of 29 in the Dow Theory track
19941-6 pp.Next on Dow TheoryScore industrial and transport sync before calling an intermediate-trend signalConfirmation is a two-average breadth test: an important swing is treated as more reliable when the industrial and transportation averages advance or decline together in both direction and intensity.
All readings on this track · 29 readings
  1. 1982A bounded-risk entry separates a forecast from a trend
  2. 1984Critiquing reward bias, single-scale charts, and exact-turn forecasts
  3. 1990Constructing dual-average primary-trend confirmation
  4. 1991Two-average confirmation before a primary reversal call
  5. 1991Delayed confirmation is not Dow Theory divergence
  6. 1991Confirmation delay and breadth divergence in a two-average case
  7. 1992Utilities as a rate-regime lead for equities
  8. 1992Critiquing unconfirmed Dow rallies with volume
  9. 1993When Dow Theory signals fail after the decision-makers change
  10. 1994Market life expectancy as a risk filter
  11. 1994Score industrial and transport sync before calling an intermediate-trend signal
  12. 1997A 1995 industrial-average breakout mapped from component trends
  13. 1998Confirm Dow trends with Market breadth and Head and shoulders
  14. 1999Confirming an equity idea with rate, commodity, and index spreads
  15. 2001Why trend, range, and Dow rules need separate tests
  16. 2001Bear-market confirmation via prior correction troughs
  17. 2002Constructing a Dow line before breakout confirmation
  18. 2002Two-average confirmation as a swing-by-swing classroom drill
  19. 2002Withhold the hypothesis until the second average confirms: a 2001 case
  20. 2002A primary-bear case study in cycle speed, Dow theory, and pattern legs
  21. 2003Four index proxies as a bear-regime dashboard
  22. 2004Dual-average confirmation at shared prior highs
  23. 2004Confirmation as the second clock on a trend break
  24. 2004The confirmation-reaction planning window after a joint break
  25. 2005Dow confirmation as a two-average trend test
  26. 2008Related-average confirmation lag after a correction
  27. 2008Intermediate confirmation outranks secular phasing
  28. 2012Align swings to nested energy regimes
  29. 2016From nonconfirmation to a bearish primary trend change
By fieldStops and loss limits40 readingsBy year199483 readings
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