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Political Districting to Minimize County Splits

Author

Listed:
  • Maral Shahmizad

    (Industrial Engineering and Management, Oklahoma State University, Stillwater, Oklahoma 74078)

  • Austin Buchanan

    (Industrial Engineering and Management, Oklahoma State University, Stillwater, Oklahoma 74078)

Abstract

When partitioning a state into political districts, a common criterion is that political subdivisions, like counties, should not be split across multiple districts. This criterion is encoded into most state constitutions and is sometimes enforced quite strictly by the courts. However, map drawers, courts, and the public typically do not know what amount of splitting is truly necessary, even to satisfy basic criteria, like contiguity and population balance. In this paper, we provide answers for all congressional, state senate, and state house districts in the United States using 2020 census data. Our approach is based on integer programming. The associated codes and experimental results are available on GitHub.

Suggested Citation

  • Maral Shahmizad & Austin Buchanan, 2025. "Political Districting to Minimize County Splits," Operations Research, INFORMS, vol. 73(2), pages 752-774, March.
    • Handle: RePEc:inm:oropre:v:73:y:2025:i:2:p:752-774
    DOI: 10.1287/opre.2023.0094
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    References listed on IDEAS

    as
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