Documenting Data Cleaning Decisions

Summary

Writing down what you changed and why — missing-value handling, outlier decisions, deduplication logic — so your analysis is reproducible and defensible when someone questions a number.

• 1Add a 'data cleaning log' section to your next analysis, listing every transformation made.
• 2Practice explaining a cleaning decision to a skeptical stakeholder in one sentence.
• 3Keep your raw and cleaned data separate so the transformation is always auditable.