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Sample size

Ten trades is a coin-flip story. A few hundred is a start. Small samples can look brilliant or terrible just by luck.

Always ask: how many trades, over what period, in which markets? And did the result survive on fresh data? See In-sample vs out-of-sample.

Related

• P-hacking and data snooping
• Overfitting
• Expectancy
• Win rate

Sources & studies

1. Investopedia (secondary): Sample

Trading termsP-hacking and data snoopingOverfitting

Last checked: 2026-11-04 · Educational, not financial advice.

Education only, not financial advice. No signals. Backtests are hypothetical: real trading can be worse. Past results don't predict future results.