The Commerce Department just issued an order banning "noise infusion"-the practice of adding small random values to published statistics to protect the confidentiality of census respondents. Going forward, the Census Bureau must use "coarsening" (rounding, aggregating, suppressing data) instead.
Lots of unanswered questions-including why the Commerce Department made this call, whether coarsening alone can meet the Bureau's statutory confidentiality obligations under Title 13, and what it means for small-area data users. Worth noting: the Census Bureau's own research found that older methods like data swapping weren't designed to defend against modern database reconstruction and reidentification attacks, which have grown more sophisticated since 2020.
📰 Hansi Lo Wang has the story: https://hansilowang.com/ 📄 Full order: DAO 216-26 📚 New to this topic? PRB has a good explainer: Disclosure Avoidance in the 2020 Census 📘 Why the Census Bureau chose differential privacy: Census Bureau brief
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Mark Mather
Associate VP
PRB
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