Interactive publication
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K-anonymity thresholds
Reporting a cell-level metric is only privacy-safe if at least k individuals share that cell/attribute combination; enforcing k only on the cell dimension while ignoring cross-tabulation with other dimensions (age, segment) can still expose small groups.
Class
Case to account for
Affects
3 conversions
01
Detection
Any reporting cut (cell x segment x time) with fewer than k unique individuals, even if the marginal cell total meets k alone.
02
Mitigation
01
Enforce k-anonymity on every cross-tabulated cut that will be published, not just the top-level cell total
02
Suppress or merge categories in any cut that falls below k
03
Affected conversions
PointH3
OPENRasterH3
OPENAdmin polygonsH3 (weighted crosswalk)
OPENMore in Privacy
Consent-based precision reductionDeclared unit below the precise-location thresholdDevice trajectory exposureDifferential privacy noise calibrationHousehold-level targeting riskMinimum aggregation windowRegional privacy restrictionsResolution degradation policySmall-cell re-identification riskSparse-audience suppressionTemporal leakage