Backtesting Overfitting Issues

Overfitting

⎊ Backtesting overfitting issues arise when a trading strategy appears profitable during historical simulation, yet fails to generalize to live market conditions. This discrepancy stems from the model adapting to random noise or specific characteristics unique to the backtesting dataset, rather than identifying genuine predictive signals. Consequently, performance metrics derived from backtesting—such as Sharpe ratio or maximum drawdown—become unreliable indicators of future results, potentially leading to substantial capital loss.