Scope of DAS

Suppressing table cells that might reveal individually identifiable data is one method used by Federal agencies to protect sensitive data. While auditing software such as the FCSM's DAS do not identify cells for suppression, the software does find the lower and upper bounds on the values of a withheld (suppressed) cell, among other useful measures.

Inter-Agency Development of DAS

While the Energy Information Administration took the lead in developing this statistical confidentiality tool, the importance of protecting privacy is evidenced by the joint financial and technical support provided by seven Federal statistical organizations in this effort. Key participants include:

• Bureau of Labor Statistics;
• Bureau of Economic Analysis;
• Bureau of the Census;
• National Center for Education Statistics;
• Internal Revenue Service;
• National Science Foundation; and the
• Energy Information Administration.

About the Disclosure Auditing System

The purpose of the application is to identify upper and lower bounds of the suppressed cells by optimization within tabular data using linear programming. The application is designed to allow a user to import CSV (comma-separated values) or MPS (IBM standard input format) data along with the structure (e.g., dimensions and hierarchies, if any) describing the tabular data.

Imported files must adhere to strict structural standards and are processed through an import and verification routine to ensure the data conforms to standards. In addition to optimizing suppressed-cell estimates, the application creates quality warnings and displays the input tables, the output solution tables, and the administrator application control tables.

Computing Requirements

A user must have the following software configured on a PC or workstation in order to run the application:
The SAS System, version 8.2 (or higher), installed on the local PC or Workstation with the following components:

• SAS/ACCESS to PCFF (PC File Formats)
• SAS/Connect
• SAS/OR
• SAS/FSP
• Microsoft Windows 95 / 98 / 2000 / NT 4.0+ or UNIX
• TCP/IP or network connection if using a client / server configuration.

Installation Setup

The application is equipped with an installation wizard to guide the user easily through the install process. To begin:

• Download and unzip the application files from the FCSM website.
• Locate the SETUP.EXE file in the directory where you unzipped the application files.
• Use Microsoft Windows Start, Run, and Browse functions to find and run SETUP.EXE.
• The executable file will begin the installation process.

If you are using a network installation, the system administrator should communicate where the application should be installed. Please be aware that DAS installs with a User's Guide that is formatted in both pdf and MS Word formats (UsersGuide.pdf and UsersGuide.doc).

Warning: one file "cdac_demo_rfp.csv" that is provided for testing does not contain all the required information and should not be used with DAS.

Disclaimer

Neither the United States government nor any of the following:

• the Office of Management and Budget,
• the Federal Committee on Statistical Methodology,
• the Confidentiality and Data Access Committee,
• the Department of Energy,
• the Energy Information Administration,
• Bureau of Labor Statistics,
• Bureau of Economic Analysis,
• Bureau of the Census,
• National Center for Education Statistics,
• Internal Revenue Service,
• National Science Foundation.

or any of their employees makes any warranty (including warranty of merchantability or fitness for a particular purpose), express or implied, for direct, indirect, incidental, or consequential damages or lost profits, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or any product or process resulting from the use of this computer software and associated materials, or represents that its use would not infringe privately owned rights, including intellectual property rights.