Tactics for Reducing the Risk of Disclosure Using the NCES DataSwap Software

• Activity Number: 462
• Type: Topic Contributed
• Date/Time: Wednesday, August 9, 2006 : 2:00 PM to 3:50 PM
• Sponsor: Section on Survey Research Methods
• Author(s): Thomas Krenzke*+ and Stephen E. Roey and Sylvia Dohrmann and Leyla Mohadjer and Wen-Chau Haung and Steve Kaufman and Marilyn Seastrom
• Companies: Westat and Westat and Westat and Westat and Westat and Retired and National Center for Education Statistics
• Keywords: confidentiality ; statistical disclosure control

Abstract

The National Center for Education Statistics (NCES) developed statistical guidelines for reducing the risk of disclosure prior to release of microdata. Among the standards is the requirement for data swapping, which is used to perturb (or mask) the data to reduce the risk of disclosing the identity of individuals or entities without impacting aggregate data. Working with NCES, Westat addressed several issues relating to complex surveys while enhancing the NCES standardized swapping software, DataSwap. This paper discusses data-swapping tactics for reducing the risk of disclosure (such as in high-risk domains, high-risk variables, hierarchical data structures), maintaining data consistency (e.g., handling skip patterns and recodes), and maintaining data quality (addressing missing data in swapping variables, controlled swapping approaches).