All Times ET
Program is Subject to Change
Modernizing EIA’s Cell Suppression Software Used in Disclosure Limitation (308012)*David Kinyon, U.S. Energy Information Administration
Keywords: disclosure limitation, cell suppression, linear programming, energy surveys
As part of a five-year plan for improving the statistical methodologies that are used for energy programs conducted by the Office of Energy Statistics, the U.S. Energy Information Administration (EIA) began the process of modernizing the cell suppression software used for disclosure limitation in March 2017. For some electric power surveys, the Monthly Biodiesel Production Survey, and the Monthly Photovoltaic Module Shipments Report, EIA has been using a variation of Robert Jewett’s program, which was acquired from the National Agricultural Statistics Service and called Disclosure Analysis (DiAna) software, to identify complementary suppressions required to protect sensitive cells of data. For structures that are more complicated than simple two-dimensional tables, the network flow methodology used in Jewett’s software is known to either under-suppress or over-suppress the number of cells that are required to protect sensitive cells. Per a Memorandum of Understanding between EIA and the Census Bureau signed in June 2017, EIA acquired the research prototype of the Census Bureau’s linear programming (LP) cell suppression software in July 2017 because it is better able to support multidimensional tables and can ensure that identifiable and sensitive data are not disclosed in linked tables. To test the prototype in the legacy production environment starting in December 2017, EIA purchased licenses for AMPL with CPLEX. After about a year of testing and programming enhancements, EIA successfully used a modified version of the Census Bureau’s LP prototype in February 2019 to perform disclosure analysis in production for year-end estimates of 2018 U.S. photovoltaic module shipments by state and territory. EIA is currently developing a plan for migrating to the Census Bureau’s LP prototype as part of its software modernization effort for the integrated Monthly Biodiesel Production Survey/Monthly Oxygenate Report.