Glossary/
Backtesting

Overfitting

Definition

When a strategy is too closely tailored to historical data, capturing noise rather than genuine patterns. Overfit strategies perform well in backtests but poorly in live trading.

Example

A strategy with 50 parameters perfectly fit to 6 months of data is likely overfit and won't generalize to future markets.

How Gilito AI Uses It

Walk-forward validation is our primary defense against overfitting. Strategies must prove themselves on out-of-sample data to receive high Gilito Scores.

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