Leakage Prevention

Leakage prevention is one of the most critical engineering disciplines in preprocessing and modeling. Scaling before the train-test split, using variables too close to the target, or incorporating future information in time-based problems all create leakage. Such mistakes make models appear much stronger than they actually are. Strong leakage prevention requires transformations to be applied in the correct order within a pipeline and time logic to be preserved rigorously. Reliable modeling depends on honest data flow design before it depends on algorithm choice.