Redistricting: Drawing the Line
arXiv:1704.03360
Abstract
We develop methods to evaluate whether a political districting accurately represents the will of the people. To explore and showcase our ideas, we concentrate on the congressional districts for the U.S. House of representatives and use the state of North Carolina and its redistrictings since the 2010 census. Using a Monte Carlo algorithm, we randomly generate over 24,000 redistrictings that are non-partisan and adhere to criteria from proposed legislation. Applying historical voting data to these random redistrictings, we find that the number of democratic and republican representatives elected varies drastically depending on how districts are drawn. Some results are more common, and we gain a clear range of expected election outcomes. Using the statistics of our generated redistrictings, we critique the particular congressional districtings used in the 2012 and 2016 NC elections as well as a districting proposed by a bipartisan redistricting commission. We find that the 2012 and 2016 districtings are highly atypical and not representative of the will of the people. On the other hand, our results indicate that a plan produced by a bipartisan panel of retired judges is highly typical and representative. Since our analyses are based on an ensemble of reasonable redistrictings of North Carolina, they provide a baseline for a given election which incorporates the geometry of the state's population distribution.
Corrected typos from previous version; added new plots showing stability; corrected error in EG plots and analysis
References in corpus (1)
Cited by in corpus (8)
- A partisan districting protocol with provably nonpartisan outcomes
- Reconfiguration of Connected Graph Partitions
- Multi-Scale Merge-Split Markov Chain Monte Carlo for Redistricting
- Non-reversible Markov chain Monte Carlo for sampling of districting maps
- Geometry of Graph Partitions via Optimal Transport
- A partial differential equations approach to defeating partisan gerrymandering
- Utility Ghost: Gamified redistricting with partisan symmetry
- Fair redistricting is hard