Providing political insight

released 10.02.07

By Tracy Culumber, NCSA

NCSA research scientist Wendy K. Tam Cho is tackling a 'computationally intractable problem' by developing a framework to analyze the 'astronomical number' of redistricting options.

"In a normal democracy, voters choose their representatives. In America, it is rapidly becoming the other way around."
   -- The Economist, April 27, 2002, referring to the 2000 congressional redistricting

Every 10 years, lawmakers remap voting districts in response to population shifts. This process is frequently contentious, with various political parties and constituencies often accusing one another of gerrymandering, or manipulating legislative lines to their respective advantages.

Wendy K. Tam Cho, an associate professor in the departments of Political Science and Statistics at the University of Illinois at Urbana-Champaign and a senior research scientist at the National Center for Supercomputing Applications (NCSA), is developing a computational tool that will create accountability and make the redistricting process more transparent.

"The impact of partisan gerrymanders on democratic rule is not well understood, but we take no sides on the societal consequences of the practice of redistricting," Cho wrote in the proposal that launched her project with NCSA. "Instead, we recognize that these questions are important and need to be analyzed with the proper tools and a unified theoretical framework."

Legislative and congressional districts must be of equal population. With this as the only constraint, there is a huge number of possible redistricting configurations, creating a computationally intractable problem.

"There is an astronomical number of possible redistricting plans," Cho said. "The redistricting problem is ideally handled by computers and not humans, since humans cannot optimize their options as well as computers."

Once completed, Cho's computational model will be able to objectively evaluate proposed redistricting plans. This will give users the ability to create redistricting plans that satisfy any objective, including maximally competitive or maximally biased districts.

While some political analysts believe that competitive districts are superior, others disagree; Cho takes no position in this debate. Instead, she says the intent of her work is simply to create a free, widely accessible redistricting tool that can be used by any interested party, opening up the redistricting process and creating accountability.

Although she is still finalizing algorithms for the program, Cho plans to have the project completed in time for the 2010 redistricting. She has formed a broad cross-disciplinary team, including computer science professor Sheldon Jacobson and mathematics professor Doug West.

Noshir Contractor, a professor of behavioral sciences at Northwestern University and an adjunct researcher at NCSA who discussed graph theories and models with Cho, explained that her research is effectively challenging social scientists to develop larger-scale social models. Contractor says her research and similar ideas are expanding the relationship between computational technology and social sciences.

"Wendy's work will bring much greater empirical rigor to the issue of political redistricting, which is currently based on opinions rather than empirical facts," Contractor said. "In doing so, it will improve and make more transparent the societal dialogue about democratic processes."

Cho also plans to develop a cyberenvironment for redistricting that will "illuminate the foundations of democracy for students," and serve as an example of how data can be properly stored and therefore be easily accessible to users through a Web interface. She added that this technology will make the concept of redistricting much easier for children to understand and will encourage them to approach social science issues in the context of computation.