A computed answer — not an opinion. Here's what nearly two decades of honest data say.
There may be something here, but it isn't robust. Don't size into it yet.
We ran the 2.5-sigma Bollinger Band breakout through an honest backtest — nearly two decades of survivorship-free NIFTY & BANKNIFTY data, out-of-sample, with real costs. The verdict: 61.8/100 — plausible but fragile. There may be something here, but it isn't robust. Don't size into it yet.
Here's where it breaks:
Five statistical tests, no mercy: out-of-sample decay (is the edge curve-fit?), Monte-Carlo robustness (is it just luck?), real cost & slippage survival, survivorship-bias exposure, and sample-size adequacy. Run on NIFTY 50 and BANKNIFTY — survivorship-free by construction, the most honest data available — across roughly two decades. Rules are read at each day's close and filled the next open, so the strategy can never peek at the bar it trades on.
See the full breakdown — free
Run the 2.5-sigma Bollinger Band breakout live, pick your market, and get its honest score plus all five tests in about 10 seconds — no signup needed to see the score.
Run the 2.5-sigma Bollinger Band breakout now →On a true, survivorship-free test (61.8/100, plausible but fragile), the 2.5-sigma Bollinger Band breakout is fragile. A backtest looking profitable is not the same as a strategy being real — most aren't. Test your own version free at The Honest Quant.
This verdict was computed on NIFTY 50 and BANKNIFTY index data (survivorship-free) over nearly two decades. It scored 61.8/100 — plausible but fragile.
Our overfitting test checks how much of the edge survives out-of-sample. See the full breakdown — and run your own parameters — in the lab.
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Educational, not financial advice. An honest backtest score measures whether a result survives statistical scrutiny — it does not predict future profit, and is not a buy or sell signal. · About · FAQ · All strategies