Guides
Backtesting & anti-overfitting guides
Plain-English guides to backtesting a trading strategy and proving the edge is real — overfitting, Walk-Forward, Monte-Carlo and more.
What is overfitting?
Overfitting is why most backtests lie. Learn what overfitting is, how to spot it, and the four tests that prove an edge is real: out-of-sample, Walk-Forward, Monte-Carlo and the Deflated Sharpe ratio.
How to backtest a strategy
A step-by-step guide to backtesting a trading strategy honestly — with no code. Define rules, use realistic costs and slippage, read the right metrics, and validate out-of-sample so the result isn't overfit.
Walk-Forward analysis
Walk-Forward analysis re-optimizes on a rolling in-sample window and trades the next unseen segment, stitching a 100% out-of-sample equity curve. Learn how it works, anchored vs rolling, and how to read the result.
Monte-Carlo simulation
Monte-Carlo simulation reshuffles your trades hundreds or thousands of times to estimate how much of a backtest was luck — the probability of profit, plausible drawdowns and risk of ruin. Learn how to read it.