Future Functions as a Cause of Missing Recent Backtest Signals

Summary

This brief BigQuant support exchange addresses a question about a backtest whose logs and apparent trade signals stop before the requested end date. The user says the run was set through the 23rd, exchange data stopped at the 17th, and the output log stopped at the 16th despite historical rebalancing activity. The response attributes the behavior to use of a future function, meaning strategy logic may depend on data that would not have been available at the time of a decision.

The exchange does not include the strategy code, identify the specific function, or explain how the suspected lookahead affects the log dates. An engineer asks to inspect the trading logic and requests that the strategy be shared for diagnosis. Thus, the answer is a plausible warning about future-data leakage rather than a demonstrated root cause or a complete debugging procedure. It supplies no backtest results or corrective implementation. Researchers should inspect data timing and indicator calculations, then verify that each signal uses only information available at that point in the simulation.

Key ideas

• The exchange attributes missing recent backtest signals to possible use of a future function.
• A future function can introduce information that would not have been available when a simulated trade decision was made.
• The question reports that logs ended before the requested backtest end date.
• The strategy code was not provided, so the proposed cause is not independently verified.
• Diagnosis requires inspecting the trading logic and the timing of its data inputs.

Tags

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.