Do the fixed rules pass only at their textbook settings?
12 November 2026 · a study on MonsterDesk's own paper account and its own tests
- Question
- When we ran this, half of the account followed one fixed rule and two more ran in simulation. Each was tested at the settings from the book it came from. A rule that passes with a 200-day average but fails at 175 and 225 passed by luck.
- What we did
- Moved every setting around its published value, 151 versions of six rules in all, and changed nothing else: the same prices, the same costs and the same pass line over the last ten years. The verdicts were fixed before the run: steady if at least 80% of a rule's versions pass, fragile if fewer than half do.
- What it showed
- The three rules we use held all around their settings.
One caution. In the years before the last ten, every version of the two trend rules was weaker: a Sharpe ratio of 0.3 to 0.6, against 0.9 to 1.1 in the last ten. The last ten years were kind to this kind of rule, and we expect less than the ten-year figures show.
Rule Versions that pass Verdict Worst fall, best to worst S&P 500 and Nasdaq-100 trend (half the account) 8 of 9 Steady 18% to 28% Eight-market trend basket (a quarter of the account from 12 November) 9 of 9 Steady 9% to 12% Buy the dip in an uptrend (simulation) 31 of 36 Steady 8% to 14% Strongest sectors, monthly 36 of 72 Mixed 17% to 34% US or overseas shares, otherwise bonds 0 of 16 Fragile 27% to 35% Bitcoin and Ether trend 0 of 9 Fragile 52% to 64% - What changed
- The eight-market trend basket now has a quarter of the paper account, beside the first rule's half, and the agents share the rest. It buys as cash comes free; nothing was sold to make room for it. The sector rule stays out.
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