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Strategy #0000000089 · Trend following and technical rules

Percentage filter trend rule
Set recent high/low, current price, filter percentage, assumed exit price and costs to see whether it triggers.

Alexander’s filter rule buys after price rises x% from a recent low and sells or reverses after it falls x% from a recent high. Later studies vary the extreme window, filter size, holding period and market. Filters reduce small-move trades but delay entries and can whipsaw; historical rule tests need data-mining controls.

Beginner-friendlyAbout 8 minutesEvidence and practical analysis

Three ways in

Understand the story. Then inspect the risk.

Start with a familiar situation, check the payoff, then test how the numbers change.

The idea · in two minutes

What is scenario P&L after a percentage filter triggers from a recent extreme?

Alexander’s filter rule buys after price rises x% from a recent low and sells or reverses after it falls x% from a recent high. Later studies vary the extreme window, filter size, holding period and market. Filters reduce small-move trades but delay entries and can whipsaw; historical rule tests need data-mining controls.

Set recent high/low, current price, filter percentage, assumed exit price and costs to see whether it triggers.

No historical price series is loaded; gaps, reversals and execution slippage are not modelled.

  • Signal inputSet recent high/low, current price, filter percentage, assumed exit price and costs to see whether it triggers.
  • Return scenarioNo historical price series is loaded; gaps, reversals and execution slippage are not modelled.

Illustrative research examples only. They are not live signals or a recommendation.

Variants · same family, different risk levers

Signals within a family use different assumptions.

Compare horizon, frequency and trend/fade interpretations.

Related strategyRelationshipWhat changesNew cost or risk
Base indicatorTechnical signalAlexander’s filter rule buys after price rises x% from a recent low and sells or reverses after it falls x% from a recent high. Later studies vary the extreme window, filter size, holding period and market. Filters reduce small-move trades but delay entries and can whipsaw; historical rule tests need data-mining controls.No historical price series is loaded; gaps, reversals and execution slippage are not modelled.
Confirmation versionMulti-indicator filterAdd trend or volume confirmation.Confirmation can delay entry.
Contrarian versionMean reversionFade extreme deviations.Can lose while a strong trend persists.

No historical price series is loaded; gaps, reversals and execution slippage are not modelled.

Read beyond the summary

References

Primary sources and research used to describe the strategy and its limits.

  1. 01Alexander (1961), Price Movements in Speculative Markets: Trends or Random Walksresearch