https://rollbrains.com/tags/python/ Recent content in Python on rollbrains Hugo en Thu, 11 Jun 2026 00:00:00 +0000 https://rollbrains.com/tradingview/backtest/lookahead-bias-penetration/ Sun, 31 May 2026 00:00:00 +0000 https://rollbrains.com/tradingview/backtest/lookahead-bias-penetration/ Discover the three systemic defects of AI-generated backtests—daily ATR leakage, dynamic stop-loss illusions, and Pandas offset snooping—and implement robust causality boundaries to prevent live trading bankruptcy. https://rollbrains.com/tradingview/backtest/slippage-simulation/ Mon, 01 Jun 2026 00:00:00 +0000 https://rollbrains.com/tradingview/backtest/slippage-simulation/ Expose the hidden execution ruin caused by guaranteed limit fill assumptions and static flat slippage. This guide presents non-linear power-law market impact models and virtual queue probability filters to align backtest simulators with live order book microstructure. https://rollbrains.com/tradingview/backtest/regime-sync-self-audit/ Thu, 11 Jun 2026 00:00:00 +0000 https://rollbrains.com/tradingview/backtest/regime-sync-self-audit/ A reader asked us to re-check our Nasdaq-corn hedging study with DCC-GARCH. We did, across 6,467 trading days (2000–2026). The claimed 5-day-lag negative correlation could not be reproduced with real data — cross-correlation sits at +0.07 to +0.09 at every lag — and the original GARCH table turned out to be a pipeline error. This is the full forensic record. https://rollbrains.com/quant/crypto-backtest-five-graveyards/ Thu, 04 Jun 2026 00:00:00 +0000 https://rollbrains.com/quant/crypto-backtest-five-graveyards/ Five ways a crypto perpetual-futures backtest lies. Two are crypto-specific—funding drag and data gaps—and fixed here in this methodology guide.