Direct Answer
Reflex is a John Ehlers oscillator that measures how far the smoothed price departs from a straight line drawn between its current and N-bar-ago values. It reacts to cycle content faster than Trendflex because it removes the linear trend over the window. Positive values show the smoothed series bulging above its own straight-line path across the window and negative values show it sagging below it.
Reflex Indicator: Formula, Meaning, Signals, Examples and How to Use It
How Is Reflex Indicator Calculated?
Reflex is a John Ehlers oscillator that measures how far the smoothed price departs from a straight line drawn between its current and N-bar-ago values. It reacts to cycle content faster than Trendflex because it removes the linear trend over the window.
Formula: Filt = SuperSmoother(price, N/2); Slope = (Filt[N] - Filt[0]) / N; Sum = (1/N) * sum over k=1..N of (Filt[0] + k*Slope - Filt[k]); Reflex = Sum / sqrt(MS)
Inputs:
- Close prices
- Lookback length N
- Super Smoother cutoff period (commonly N/2)
Reading it. Positive values show the smoothed series bulging above its own straight-line path across the window and negative values show it sagging below it. Zero crossings mark changes in that curvature. Because the linear trend is removed, readings emphasize cycles over drift.
Limits. Normalization by a running RMS makes values relative, and the straight-line baseline can be misleading when a window contains a single large jump. The smoothing step adds some lag.
What is Reflex Indicator?
Reflex is a John Ehlers oscillator that measures how far the smoothed price departs from a straight line drawn between its current and N-bar-ago values. It reacts to cycle content faster than Trendflex because it removes the linear trend over the window.
How to use Reflex Indicator
Positive values show the smoothed series bulging above its own straight-line path across the window and negative values show it sagging below it. Zero crossings mark changes in that curvature. Because the linear trend is removed, readings emphasize cycles over drift. A reading alone is never a buy or sell signal; it needs context from price structure, volume, volatility and the broader market regime.
Strengths
- Subtracting a straight line between the current and N-bar-ago values measures curvature in the window rather than the net move, so trending drift is removed.
- The same RMS normalization used for Trendflex keeps readings in comparable units over time.
- Reproducible when the formula and data convention are fixed.
Weaknesses and limitations
- The baseline connects only two points, so any noise at an endpoint tilts the line and changes every term in the sum.
- A slow, steady trend produces readings near zero by design, so the oscillator is quiet exactly where a trend indicator would be active.
- Correlated indicators can create false confidence by repeating the same underlying information.
Editorial and risk note
This page is educational content, not individualized investment advice. It should not imply guaranteed prediction, accuracy or outperformance.
Frequently Asked Questions
Is Reflex Indicator a buy or sell signal?
No. Positive values show the smoothed series bulging above its own straight-line path across the window and negative values show it sagging below it. Normalization by a running RMS makes values relative, and the straight-line baseline can be misleading when a window contains a single large jump. A trade built on it still needs a trigger, an invalidation rule, a position size and realistic execution assumptions.
What is the best setting for Reflex Indicator?
Reflex Indicator takes these inputs: close prices; lookback length N; super Smoother cutoff period (commonly N/2). There is no universal best setting for the tunable ones, so test them across instruments, regimes and out-of-sample periods and favor stable parameter regions over one historical winner.
Can Reflex Indicator be used by itself?
Normalization by a running RMS makes values relative, and the straight-line baseline can be misleading when a window contains a single large jump. The smoothing step adds some lag. For that reason it is read next to measures of direction, participation, valuation, liquidity and risk, not alone.
Does Reflex Indicator work on every timeframe?
The calculation (Filt = SuperSmoother(price, N/2); Slope = (Filt[N] - Filt[0]) / N; Sum = (1/N) * sum over k=1..N of (Filt[0] + k*Slope - Filt[k]); Reflex = Sum / sqrt(MS)) can be run on any bar size, but behavior is not portable: a reading on a five-minute chart describes a very different market window from the same reading on a daily chart. Validate the exact timeframe before relying on it.
Why does Reflex Indicator give false signals?
The baseline connects only two points, so any noise at an endpoint tilts the line and changes every term in the sum. A slow, steady trend produces readings near zero by design, so the oscillator is quiet exactly where a trend indicator would be active. Lag, noise and regime changes add to this, because market participants react to new information after the reading is calculated.
How should Reflex Indicator be backtested?
Rebuild Reflex Indicator from close prices using point-in-time data, write the rules before testing, include delisted securities where relevant, model realistic fills and costs, reserve a validation sample and compare with a simpler baseline.