Honest back-testing

Costs, biases and the numbers that matter

Professional - Gold & Platinum

In this lesson

Include realistic costs and avoid look-ahead and survivorship bias so back-test results mean something.

Key takeaways

Include fees and slippage on every trade; high-frequency strategies are most sensitive.
Look-ahead bias uses information not available at the time.
Survivorship bias ignores delisted or failed assets; data snooping finds luck.
Judge maximum drawdown, expectancy, trade count and losing-period length — not just total return.

Watch this lesson with Tessa. The full video, worked example, calculator, quiz and Ask Tessa are part of Money Globe X Gold and Platinum. Create your account to start learning.

Next lesson: Overfitting and walk-forward testing

Educational information only - not financial advice.

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