2004issue C121-7
Evaluating a two-window trend trigger
A scaled oscillator from two adjacent windows of highs and lows can turn a trend stance into a fully specified long, short, and stay-flat procedure. The evaluation question is whether those same rules remain usable after the lookback, market, and sample period change.
- Buy power and sell power come from two adjacent lookback windows of highs and lows, and the oscillator scales their difference by the average of those two ranges.
- Large range overlap keeps the reading near the origin; small overlap in a directional move pushes it beyond a long or short trigger.
- The same triggers become a mechanical trading system only when long, short, and stay-flat rules are specified together and tested as one object.
- Robustness testing asks whether that directional outcome survives a change of lookback, market, or time slice, rather than whether one historical sample is treated as proof.
Two adjacent windows of highs and lows
The trend-trigger-factor is a scaled oscillator that compares buy power and sell power from two adjacent lookback windows of highs and lows, then divides their difference by the average of those two windows' ranges.
Buy power is the highest high of the nearer window minus the lowest low of the farther window. Sell power is the highest high of the farther window minus the lowest low of the nearer window. That denominator is the average of the two window ranges.
Range overlap and the trigger
Range overlap is how much the two summarized lookback bars occupy the same price territory. In a consolidation the two powers are similar in size and close to the average two-window range, so the gap stays small relative to that average and the oscillator typically remains near the origin.
When the two summarized bars have little overlap in an uptrend, buy power is large and sell power is small versus the average range, so the oscillator tends to move beyond a positive trigger. In a downtrend the same overlap logic reverses: sell power is large and buy power is small, and the absolute gap between the two powers is large, so the reading tends to move beyond a negative trigger.
One procedure and three robustness checks
A trend filter stays long only when the oscillator is above a positive trigger and short only when it is below a negative trigger. Adding the stay-flat case makes a mechanical trading system: a fully specified long, short, and stay-flat procedure whose entries, exits, and abstention rules can be tested as one object.
The archive presents the oscillator as usable alone or as confirmation of other signals. It treats robustness as three checks: across parameter values, across markets, and across time.
A historical multi-market hypothetical used continuous contracts and charged commission and slippage. That table reported mixed signed totals across groups. Among the lookbacks compared, historical usefulness was not the same from one window length to another.
All readings on this track · 51 readings
- 1986Degrees of freedom in trading system optimization
- 1988Walk-forward and neighborhood tests after optimization
- 1988Undisclosed rules block system robustness tests
- 1988Testing re-optimization calendars against random parameter controls
- 1989Binary search limits on multi-peak average grids
- 1989Parameter neighborhoods that survive a shift
- 1990Use profit mapping to keep a cycle and stop plateau
- 1990Why popular indicator optimization fails robustness
- 1991Retesting weighted indicator balances across horizons
- 1992Constructing forecast models with regression, walk-forward, and robustness
- 1992Diagnose regimes before you lock parameters
- 1992When stops change system timing
- 1993Walk-forward halt rules for forecast models
- 1994Walk-forward evaluation of genetic index rules
- 1995Input pruning as walk-forward system evaluation
- 1995Critiquing neural nets as incomplete trading systems
- 1996Rebuild the equity-path ratio before it ranks a designed system
- 1996Parameter grids can fit random walks
- 1996Walk-forward analysis belongs in the design of a mechanical trading system
- 1997When a holdout fails, discard the rule set
- 1997Test rewarded rule breaks before replacing the system
- 1997Walk-forward rules keep system research from rewriting live trades
- 1999Keep a channel-breakout to two lookbacks and test neighbor stability
- 1999Constant investment size in stock system evaluation
- 2000Forcing optimization maps mechanical system failure boundaries
- 2000Robust parameter selection with surface charts
- 2001A two-gate classroom test for a two-window momentum trend filter
- 2002How a two-sided continuation factor becomes a testable trend rule
- 2002Evaluating two-window trend intensity as a reversal rule
- 2003Discounting speculative bubbles in system robustness tests
- 2003Walk-forward evaluation of locked stochastic oscillator rules
- 2003Critiquing mechanical system design after extreme price regimes
- 2004Evaluating a two-window trend trigger
- 2005Grade backtested signals with holdouts and optimization plateaus
- 2006Reserved-sample evaluation of trading system design
- 2006Walk-forward critique of hindsight crossover systems
- 2008Condition-matched walk-forward evaluation for mechanical systems
- 2011Session-split evaluation of regular and overnight systems
- 2012Walk-forward evaluation as operator rehearsal
- 2013Two-window evaluation of mechanical trading systems
- 2013Walk-forward filter selection for repeated-median velocity
- 2014Walk-forward evaluation for fading-memory velocity systems
- 2015Test oscillator events before tuning rules
- 2016Walk-forward evaluation of a five-parameter parabolic stop-and-reversal
- 2016Walk-forward optimization without curve fitting
- 2017Optimization without overfitting in trend-system evaluation
- 2017Parameter stability is a better guide than a larger crossover grid
- 2018Point-in-time universes for system evaluation
- 2018Walk-forward robustness evaluation for optimized systems
- 2018Critiquing breakout systems through robustness tests
- 2018A critique of parameter fitting in system design