Statistical Disclosure Control in Practice

1 Introduction to Statistical Disclosure Control.- 1.1 Introduction.- 1.2 The increasing importance of SDC.- 1.3 The Problems.- 1.3.1 Microdata.- 1.3.2 Tables.- 2 Principles.- 2.1 Introduction.- 2.2 Basic Concepts.- 2.3 Preliminaries on the SDC for Microdata.- 2.4 The Philosophy of SDC for Microdata.- 2.5 The World According to a Releaser of Microdata.- 2.6 SDC for Tables.- 3 Policies and Case Studies.- 3.1 Introduction.- 3.2 Options for Data Dissemination.- 3.3 SDC Policy for Microdata of Various Statistical Offices.- 3.4 The Netherlands: WSA.- 3.5 Great Britain: Samples of Anonymized Records.- 3.5.1 Samples of Anonymized Records.- 3.5.2 Confidentiality Protection in the SARs.- 3.5.3 Dissemination of SARs.- 3.6 Eurostat.- 3.7 Luxemburg Income Study.- 4 Microdata.- 4.1 Introduction.- 4.2 SDC rules.- 4.2.1 Classification of Variables.- 4.2.2 Rareness Criteria.- 4.2.3 Sensitive Variables.- 4.2.4 Household Variables.- 4.2.5 Regional Variables.- 4.2.6 The Spread of Regional Characteristics.- 4.2.7 Sampling Weights.- 4.2.8 Remaining SDC Rules.- 4.2.9 Examples of Sets of SDC Rules.- 4.3 SDC for Microdata Sets in Practice.- 4.3.1 SDC Measures.- 4.3.2 Matching Microdata Sets.- 4.3.3 The Use of a Larger Microdata Set.- 4.3.4 Continuous Variables.- 4.3.5 Comments on the Construction of Household Files.- 5 Microdata: Backgrounds.- 5.1 Introduction.- 5.2 Estimation of Population Frequencies.- 5.3 Continuous Variables.- 5.4 Global Recoding and Local Suppression.- 5.5 Sampling Weights.- 5.6 The Re-identification Risk of an Entire Microdata Set.- 6 Tabular Data.- 6.1 Introduction.- 6.2 Tables with Magnitude Data.- 6.3 Sensitive Cells in Frequency Count Data.- 6.4 Disclosure Control Measures.- 6.4.1 Table Redesign.- 6.4.2 Cell Suppression.- 6.4.3 Feasibility Intervals.- 6.4.4 Rounding.- 6.4.5 Averages and Fractions.- 6.5 Recommendations.- 6.5.1 A Procedure for SDC of Tabular Data.- 6.5.2 Warning.- 6.5.3 Tabular Data Based on Samples.- 6.6 Linked Tables.- 7 Tabular Data:

Leon Willenborg has worked at the Department of Statistical Methods at Statistics Netherlands since 1983, first as a researcher and since 1989 as a senior researcher. Since 1989 his main field of research and consultancy has been statistical disclosure control. From 1996-1998 he was the project coordinator of the EU co-funded SDC project.