Candlestick formation · Bearish
What is it, in one line
A candle isolated by a gap up before it and a gap down after it, leaving it stranded at the high.
Bearish · 3 candles · verdict: rule and thresholds below
A candle isolated by a gap up before it and a gap down after it, leaving it stranded at the high. 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
Price gaps up into the middle candle and gaps back down out of it, so that candle's range touches neither neighbour. The abandoned price band above is what gives the formation its name and its claim.
The traditional claim
Treated as a major top signal: the gap down undoes the gap up and strands the buyers who chased the high.
How this detection is wrong
Both gaps are required. A single gap with an unrelated wide bar beside it is not an island.
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 |
| atrPeriod | bars of ATR used to size everything below | 14 |
| minGapAtr | gap between bars, at least, in ATR | 0.15 |
| minPriorSlope | prior slope must be above | 0.5 |
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.
What is a Bearish Island Reversal candlestick pattern?
Price gaps up into the middle candle and gaps back down out of it, so that candle's range touches neither neighbour. The abandoned price band above is what gives the formation its name and its claim. The detector also requires a prior uptrend, so the same shape in the wrong context is not counted.
Is the Bearish Island Reversal bullish or bearish?
It is read as bearish. Treated as a major top signal: the gap down undoes the gap up and strands the buyers who chased the high.
When is a Bearish Island Reversal not a Bearish Island Reversal?
Both gaps are required. A single gap with an unrelated wide bar beside it is not an island.
How is a Bearish Island Reversal detected?
As an executable rule over open, high, low and close, with 4 named parameters — including bars of prior trend inspected 5, bars of ATR used to size everything below 14, gap between bars, at least, in ATR 0.15 — 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 uptrend, its mirror a preceding downtrend.
Bullish Island Reversal: A candle isolated by a gap down before it and a gap up after it, leaving it stranded at the low.