Gerrymandering and Compactness: Implementation Flexibility and Abuse
Name
1803.02857.pdf
Description
Accepted version
Size
2.48 MB
Format
Adobe PDF
Checksum (MD5)
734c0d9a0ca122b62246fa2fb408c5bb
Author(s) •
Barnes, Richard
Solomon, Justin
Date Issued
2020
Journal
Political Analysis
Publisher
Cambridge University Press (CUP)
Version
Author's final manuscript
Abstract
AbstractPolitical districts may be drawn to favor one group or political party over another, or gerrymandered. A number of measurements have been suggested as ways to detect and prevent such behavior. These measures give concrete axes along which districts and districting plans can be compared. However, measurement values are affected by both noise and the compounding effects of seemingly innocuous implementation decisions. Such issues will arise for any measure. As a case study demonstrating the effect, we show that commonly used measures of geometric compactness for district boundaries are affected by several factors irrelevant to fairness or compliance with civil rights law. We further show that an adversary could manipulate measurements to affect the assessment of a given plan. This instability complicates using these measurements as legislative or judicial standards to counteract unfair redistricting practices. This paper accompanies the release of packages in C++, Python, and R that correctly, efficiently, and reproducibly calculate a variety of compactness scores.
MIT Department
Massachusetts Institute of Technology. Computer Science and Artificial Intelligence Laboratory
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1017/pan.2020.36