Data & methodology

Data before models. Method before metrics.

A backtest is conditional evidence. Its value depends on the market data, simulation rules, costs, execution model, experiment design, and the questions asked after the run.

01 / DATA

Know what the simulation is made from.

For tick-sensitive systems, bar data can hide the intrabar path that determines whether an order, stop, or state transition would have occurred. Where appropriate and available, research therefore uses real tick histories and records the source and test configuration.

Real tick data is not a guarantee of realism. Broker feed differences, gaps, symbol specifications, trading sessions, time zones, spread history, and data corrections can all change the test.

02 / DATA CHECKS

Inspect before optimising.

The exact checklist varies by instrument and strategy. These are the recurring questions.

Coverage

Is the history complete enough?

Review the intended interval, gaps, duplicated records, discontinuities, and changes in data availability.

Time

Are timestamps interpreted correctly?

Document time zone, daylight-saving changes, session boundaries, and any conversion applied to the source.

Prices

What do Bid, Ask, and spread represent?

Confirm the available fields, spread behaviour, precision, and the price used for charts versus execution.

Instrument

Do symbol settings match the test?

Record contract size, point value, margin rules, trading sessions, stops level, and other relevant specifications.

Transformations

What changed between source and test?

Track filtering, normalisation, resampling, gap handling, custom-symbol imports, and dataset versions.

Provenance

Can the input be identified later?

Keep enough source and configuration information to understand which dataset produced a result.

03 / TESTING PROTOCOL

Escalate the test as the idea survives.

  1. 01

    Specification check

    Define rules and expected behaviour before evaluating the output.

  2. 02

    Implementation diagnostics

    Use traces, targeted scenarios, and visual inspection to confirm that the code follows the specification.

  3. 03

    Baseline simulation

    Run a controlled reference test with documented data, platform settings, costs, and parameters.

  4. 04

    Robustness checks

    Vary parameters, periods, market conditions, and reasonable execution assumptions to look for fragile dependence.

  5. 05

    Holdout or forward evaluation

    Where the research design supports it, reserve unseen data or later observations for a separate evaluation.

  6. 06

    Review and archive

    Record the result, limitations, code and data context, and the decision to continue, revise, or stop.

A BACKTEST CAN SUPPORT

  • Whether the coded rules behaved as specified in the simulation
  • How results changed across the tested data and assumptions
  • Where trades, risks, or losses were concentrated
  • Which components merit deeper investigation

A BACKTEST CANNOT PROVE

  • Future profitability or a guaranteed return
  • That historical market structure will persist
  • That live fills, latency, and costs will match the model
  • That an untested failure mode does not exist

04 / RESEARCH NOTE

Real ticks and generated ticks are not interchangeable.

Our plain-English note explains how MetaTrader 5 test modes change the evidence a backtest contains.

Read the note