Candlestick formation · Bullish
What is it, in one line
Gaps down, then closes back at the previous close.
Bullish · 2 candles · verdict: rule and thresholds below
Gaps down, then closes back at the previous close. The engine checks the formation as an executable condition over open, high, low and close, with a trend filter applied before the count is kept.
Method
Two long candles in opposite directions whose closes land at the same level. The second opens well below the first candle’s low and recovers all of it — but only back to where the first closed, not through it.
The traditional claim
Traditionally read as a reversal in which sellers were met and exactly matched.
How this detection is wrong
A piercing line closes into the prior body; a counterattack closes level with the prior close. The matching close is the whole pattern, and the tolerance parameter decides how exact "matching" is.
Published so the count can be reproduced. Every figure below is a parameter of the rule, not a preference: change one and the occurrence count changes with it.
| Parameter | Meaning | Default |
|---|---|---|
| trendPeriod | bars of prior trend inspected | 5 |
| maxPriorSlope | prior slope must be below | -1 |
| matchTolAtr | how closely two levels must match, in ATR | 0.05 |
| minBodyAtr | body, at least, in ATR | 0.6 |
| atrPeriod | bars of ATR used to size everything below | 14 |
These share enough geometry that a detector can return more than one of them on the same bar. The engine reports every match rather than picking a winner.
Every pair on the site that can be mistaken for another, and what separates each: the look-alikes index.
Two long candles in opposite directions whose closes land at the same level. The second opens well below the first candle’s low and recovers all of it — but only back to where the first closed, not through it. The detector also requires a prior downtrend, so the same shape in the wrong context is not counted.
It is read as bullish. Traditionally read as a reversal in which sellers were met and exactly matched.
A piercing line closes into the prior body; a counterattack closes level with the prior close. The matching close is the whole pattern, and the tolerance parameter decides how exact "matching" is.
As an executable rule over open, high, low and close, with 5 named parameters — including bars of prior trend inspected 5, prior slope must be below -1, how closely two levels must match, in ATR 0.05 — all published on this page so the count can be reproduced. Strict and loose variants are defined as well, so the sensitivity of the count to those thresholds is visible rather than assumed.
Measurement pending re-run
No hit rate is published here yet. The run that would supply one was computed on engine ca6d9e36c81c; the engine is now cfb08765de7c. Its candlestick rows included the still-forming bar, and it predates the chart formations entirely, so those figures have been withdrawn rather than published with a caveat. The definition above is unaffected: it is what the detector tests, and no re-run changes it.
Same shape, opposite reading
The shapes are close, and the prior trend is what decides which one fired: this rule requires a preceding downtrend, its mirror a preceding uptrend.
Bearish Counterattack: A long up candle, then a long down candle opening far higher but closing at the same price.