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IGPA releases computer-generated legislative district map
As the Illinois General Assembly considers re-drawing legislative district boundaries that will be used for elections in the coming decade, IGPA has been investigating alternatives that could provide a more transparent and equitable map. The resulting computer-generated map shows that district boundaries can be more compact while increasing representation of minority populations in the state.
The map fulfills the rules of redistricting without political gerrymandering. Dr. Hayri Onal’s project, “Redistricting in Illinois: A Systemic Procedure and Nonpartisan Legislative District Plans,” uses a mathematical computer model to configure districts that divide populations equally for state government districts. Onal developed the computer model with graduate student Kevin T. Patrick. The research team is part the Agricultural and Consumer Economics department at the University of Illinois at Urbana-Champaign.
Onal, a professor of agricultural and consumer economics at the University of Illinois at Urbana-Champaign, and his team also created a computer-generated map using 2000 U.S. census data and compared it to the actual map that was created by the General Assembly. The researchers found that the computer model produced a map that was more representative of minority populations, more compact, and more equally divides the population.
"I think of redistricting as a mathematical challenge," Onal said at a presentation on Wednesday, May 11 at the Union League Club of Chicago. "By improving our computer methods, our research pushes the boundaries of redistricting."
A central component of the computer-generated map is consideration of minority representation. The 2010 census data shows that the black population in Illinois increased slightly, while the Hispanic population increased from about 12% to over 15%. Onal's model found a way to create five Hispanic majority districts in the Senate and 13 Hispanic majority districts in the House. Compared to the current map, the black majority districts were maintained in the Senate (8) and decreased slightly in the House (from 18 to 15).