What is in-sample?In-Sample
The stretch of historical data used to tune parameters.
Learn “in-sample” in an animated lesson
- Quant BasicsOut-of-Sample Testing: Don't Get Fooled by Backtests
Picking the best settings on historical data is easy. The hard part is whether they still work on data they've never seen. Walk-forward testing mimics the real process of choosing settings first, then trading.
- Indicators in Practice & BacktestingParameter Optimization and Overfitting
Tuning settings to the historical "best" often just memorizes noise. Out-of-sample testing is the real test.
Related terms
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