Backtest Hygiene Checklist
Hygiene comes before validation. A backtest can pass an out-of-sample test and still be worthless if the underlying simulation leaks the future or ignores costs. Walk this list once when you build the harness, then re-confirm it whenever you add a new data source or feature.
Checklist Progress
Move item by item and keep your place
Progress saves locally, so you can work through the page over multiple sessions without resetting your checklist.
Checklist Sections
Work in focused batches instead of one long wall
Section 1
Phase 1: Data integrity
Section 2
Phase 2: Look-ahead and alignment
Section 3
Phase 3: Cost realism
Section 4
Phase 4: Reproducibility
Pro Tips
Small moves that make the checklist easier to finish
Try These Tools
Run the numbers next
Walk-Forward Validator
Upload a returns CSV. Rolling or expanding IS/OOS windows, per-window Sharpe, walk-forward efficiency, and a concatenated OOS equity curve. Catches regime.
Backtest Overfitting Score
Upload a backtest trade log and compute Probability of Backtest Overfitting (PBO), Deflated Sharpe Ratio, and the odds your edge survives live trading.
Synthetic Market Data Generator
Generate synthetic price series — geometric Brownian motion, GARCH(1,1) with volatility clustering, regime-switching bull/bear, or copula-linked.
Sources & References
- The Probability of Backtest Overfitting — Bailey, Borwein, Lopez de Prado, Zhu, Journal of Computational Finance (2017)
- Advances in Financial Machine Learning — Marcos Lopez de Prado, Wiley (2018)
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