Protecting Census 2021 Origin-Destination Data Using a Combination of Cell-Key Perturbation and Suppression

  • Iain DoveEmail author
  • Christos Ntoumos
  • Keith Spicer
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11126)


The UK Office for National Statistics (ONS) is intending to produce outputs involving travel to and from different locations (origins and destinations) in 2021, as they have done for previous Censuses. This data poses a particular challenge for protecting against disclosure risk, as categorising respondents on multiple geographical variables yields very sparse tables. This paper explores the disclosure risk and data utility of one option for protecting this data: applying cell-key perturbation (noise), and suppressing the remaining disclosive values. It finds that these methods provide good protection for the data with considerable loss of utility for outputs at low geographies. Whether this is an acceptable approach will be determined by user feedback.


Origin destination Flow data Cell-key perturbation Suppression 


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Copyright information

© Crown 2018

Authors and Affiliations

  1. 1.Office for National StatisticsTitchfieldUK

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