OPEN-SOURCE SCRIPT
PBO / Selection Bias Calculator

A calculator for selection bias in strategy backtests, based on the False Strategy Theorem. Enter the number of strategy variants you searched, the variance of their Sharpe ratios, and your single best variant's Sharpe; it returns the expected maximum Sharpe a no-edge search of that size would produce, and flags whether your best clears that screen.
How to read it
If your best Sharpe does not beat the expected maximum under the null, it is plausibly just the luckiest of many trials. Important: clearing the expected maximum is a screening threshold, not a statistical significance test.
Honest by design
- No buy/sell signals. It reads no price data; it is a pure analytics table computed from your inputs.
- Non-repainting by construction.
Open-source and MIT licensed. The underlying statistics (PSR, Deflated Sharpe, PBO via CSCV, Harvey-Liu haircut) follow the published papers cited in the code.
Disclaimer: impersonal educational and analytics tool. This is not investment advice, not a personalised recommendation, and carries no performance guarantee. Past results do not predict future results. You are solely responsible for your own trading decisions.
How to read it
If your best Sharpe does not beat the expected maximum under the null, it is plausibly just the luckiest of many trials. Important: clearing the expected maximum is a screening threshold, not a statistical significance test.
Honest by design
- No buy/sell signals. It reads no price data; it is a pure analytics table computed from your inputs.
- Non-repainting by construction.
Open-source and MIT licensed. The underlying statistics (PSR, Deflated Sharpe, PBO via CSCV, Harvey-Liu haircut) follow the published papers cited in the code.
Disclaimer: impersonal educational and analytics tool. This is not investment advice, not a personalised recommendation, and carries no performance guarantee. Past results do not predict future results. You are solely responsible for your own trading decisions.
Open-source script
In true TradingView spirit, the creator of this script has made it open-source, so that traders can review and verify its functionality. Kudos to the author! While you can use it for free, remember that republishing the code is subject to our House Rules.
Disclaimer
The information and publications are not meant to be, and do not constitute, financial, investment, trading, or other types of advice or recommendations supplied or endorsed by TradingView. Read more in the Terms of Use.
Open-source script
In true TradingView spirit, the creator of this script has made it open-source, so that traders can review and verify its functionality. Kudos to the author! While you can use it for free, remember that republishing the code is subject to our House Rules.
Disclaimer
The information and publications are not meant to be, and do not constitute, financial, investment, trading, or other types of advice or recommendations supplied or endorsed by TradingView. Read more in the Terms of Use.