OPEN-SOURCE SCRIPT
Basis-Filtered Lower BB

Basis-Filtered Lower BB is a modified Bollinger Band indicator designed to help locate potential long entries only, based on EdgeTools’ findings around lower-band mean reversion.
Instead of treating Bollinger Bands as breakout, squeeze, or support/resistance tools, this script focuses on downside volatility extremes. According to the referenced finding, the strongest edge came from price closing below the lower Bollinger Band, where the move may be unusually extended relative to the asset’s recent volatility regime and later revert upward.
The indicator filters the lower Bollinger Band with an offset RMA basis to reduce steep near-vertical drops during volatility expansion. The final Filtered Lower BB line shows the higher value between the lower band and the basis filter, with optional SMA smoothing enabled by default.
Features:
This is a visual research tool for identifying lower-band penetration zones, not financial advice or a complete trading strategy.
Instead of treating Bollinger Bands as breakout, squeeze, or support/resistance tools, this script focuses on downside volatility extremes. According to the referenced finding, the strongest edge came from price closing below the lower Bollinger Band, where the move may be unusually extended relative to the asset’s recent volatility regime and later revert upward.
The indicator filters the lower Bollinger Band with an offset RMA basis to reduce steep near-vertical drops during volatility expansion. The final Filtered Lower BB line shows the higher value between the lower band and the basis filter, with optional SMA smoothing enabled by default.
Features:
- Built for studying potential long-only mean-reversion entries
- EMA-based lower Bollinger Band
- Fixed 2 standard deviation multiplier
- Separate lengths for lower band and basis filter
- Percentage-based basis offset, suitable for logarithmic charts
- Smoothed filtered output
- Raw lower band and basis filter hidden by default
This is a visual research tool for identifying lower-band penetration zones, not financial advice or a complete trading strategy.
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.