QUANTHEON Lab
The Research Library

Learn to backtest like a quant desk

Plain-English guides and free tools for building trading strategies and proving the edge is real — the honest method behind QUANTHEON Lab, with nothing to install.

Guides
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. 4 min read 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. 3 min read Strategy walkthrough A full end-to-end walkthrough of the Strategy workbench: brief your AI research desk in plain English, edit the block graph, run an honest backtest and get an overfitting verdict — no code. 6 min read Portfolio walkthrough A full end-to-end walkthrough of the Portfolio Lab: start from a preset or plain English, set contributions and rebalancing, simulate on shared capital and optimize the weights without overfitting. 6 min read Shared-capital portfolio Most portfolio backtests blend independent equity curves — each holding behaves as if it had its own money. A shared-capital book runs one account where sleeves compete bar by bar, with cash redistribution and per-holding ceilings. Learn the difference and when to use it. 17 min read Multi-asset backtesting A strategy that works on one ticker is an anecdote — you found the ticker where it worked. Run the same rules across up to fifty instruments in one pass, read the aggregate and the per-asset spread, and learn why profit factor is a median and per-asset tuning is overfitting. 6 min read 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. 2 min read 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. 2 min read Deflated Sharpe ratio Deflated Sharpe ratio and PSR explained: how testing many strategies inflates the best Sharpe, and how deflating for the number of trials, skew, kurtosis and sample length gives the honest number. 5 min read Adaptive position sizing Adaptive position sizing scales your trade size with a signal — VIX, volatility, trend strength — instead of a fixed bet. Learn the four response-curve shapes, why it usually overfits, and how to test that the curve holds out-of-sample. 4 min read Custom indicators Build a custom indicator once and reuse it in any strategy. AI Import reconstructs non-standard indicators exactly (Linear Regression / LSMA, LazyBear's Squeeze Momentum) and saves them to your library — and each one shows which strategies use it. 5 min read The Strategy Score The Strategy Score explained: a free 0–100 blend of a strategy's realized metrics for fast triage — and why you must pair it with the Overfitting Polygraph verdict before trusting it. 7 min read
Free calculators
Sharpe ratio calculator Free Sharpe ratio calculator. Enter annualized return, risk-free rate and volatility to get the Sharpe ratio instantly, with a plain-English verdict. Learn what a good Sharpe ratio is and why it can mislead. 2 min read Max drawdown calculator Free maximum drawdown calculator. Paste an equity curve and get the max drawdown %, the peak and trough, and a plain-English verdict on how painful the strategy would have been to hold. 2 min read Position size calculator Free position size calculator. Enter your account size, risk per trade, entry and stop-loss to get the exact number of shares to trade and the cash you're risking. Plain-English risk management. 2 min read CAGR calculator Free CAGR calculator — the compound annual growth rate from a start value, end value and number of years, with a plain-English verdict, total return and growth multiple. 3 min read Sortino ratio calculator Free Sortino ratio calculator — the risk-adjusted score that counts only downside volatility. Enter return, target and downside deviation for an instant, plain-English verdict. 3 min read Kelly criterion calculator Free Kelly criterion calculator — optimal bet size from win probability and payoff ratio, with half-Kelly, expectancy and a risk-of-ruin reality check. 3 min read Deflated Sharpe calculator Free Deflated Sharpe ratio calculator (Bailey & López de Prado): price the search that produced your best variant. Enter the Sharpe, how many configurations you tried and the sample length to get the probability the edge is real. 4 min read
Under the hood