Common comparison error
Changing rules after viewing unseen results turns a claimed Backtest into another development pass, not Out of sample test.
GlossaryStrategy & risk
Backtest
An evaluation of fixed strategy rules against historical data using stated entry, payout, timing, and settlement assumptions. It does not prove future results.
Practical use
How to verify Backtest
Read Backtest together with Expected value, Out-of-sample test, Forward test. The comparison must preserve the exact rule, value, state, and evidence described below.
A neutral example
At 80% net payout, a 100-unit stake needs more than 55.56% wins before costs. Backtest is recomputed after refunds, fees, and Expected value states. The operative detail for Backtest is concrete: historical rules require fixed entry, payout, timing, settlement, and exclusion assumptions before results are opened.
Evidence path
Where to verify Backtest
Use the source that governs the exact contract, account, entity, or platform state. A general definition cannot replace current broker terms.