A Stochastic Search Approach to Solving the Cell Suppression Problem for Three-Dimensional Hierarchical Tables

• Activity Number: 680
• Type: Contributed
• Date/Time: Thursday, August 5, 2010 : 10:30 AM to 12:20 PM
• Sponsor: Section on Statistical Computing
• Author(s): Matt Fetter*+
• Companies: National Agricultural Statistics Service
• Keywords: stochastic search ; disclosure risk ; cell suppression

Abstract

Cell suppression is one method that is commonly used to reduce disclosure risk when data are published in hierarchical tables. A form of optimality is achieved for 2-dimensional tables by formulating the cell suppression problem as a minimum cost flow problem. There are issues with this approach in general, and for its application to 3-dimensional tables in particular. First, cell suppression is fundamentally an integer programming problem with a non-smooth cost function. Secondly, the minimum cost flow approach is not directly applicable to 3-dimensional tables. A stochastic search approach is presented that is guaranteed to generate closed paths in 3-dimensional tables. Although no claim of optimality can be made, this method is capable of finding good solutions using significantly fewer iterations than a similarly constrained blind random search.