activity
20052026
most citedGerrymandering metrics: How to measure? What's the baseline?

12 citations · 39 across the 6 of their papers we have counts for

collaborators

14 papers

math.MG2026

Metric geometry for ranking-based voting: Tools for learning electoral structure

Moon Duchin, Kristopher Tapp

In this paper, we develop the metric geometry of ranking statistics, proving that the two major permutation distances in the statistics literature -- Kendall tau and Spearman footr…

cs.CY2022★ 9 cited

Census TopDown: The Impacts of Differential Privacy on Redistricting

Aloni Cohen, Moon Duchin, JN Matthews +1

The 2020 Decennial Census will be released with a new disclosure avoidance system in place, putting differential privacy in the spotlight for a wide range of data users. We conside…

physics.soc-ph2020

Implementing partisan symmetry: Problems and paradoxes

Daryl DeFord, Natasha Dhamankar, Moon Duchin +4

We consider the measures of partisan symmetry proposed for practical use in the political science literature, as clarified and developed in Katz, King, and Rosenblatt (2020). Eleme…

math.AT2020

The (homological) persistence of gerrymandering

Moon Duchin, Tom Needham, Thomas Weighill

We apply persistent homology, the dominant tool from the field of topological data analysis, to study electoral redistricting. Our method combines the geographic information from a…

cs.SI2020

Mathematics of Nested Districts: The Case of Alaska

Sophia Caldera, Daryl DeFord, Moon Duchin +2

In eight states, a "nesting rule" requires that each state Senate district be exactly composed of two adjacent state House districts. In this paper we investigate the potential imp…

physics.soc-ph2018

Locating the representational baseline: Republicans in Massachusetts

Moon Duchin, Taissa Gladkova, Eugene Henninger-Voss +3

Republican candidates often receive between 30 and 40 percent of the two-way vote share in statewide elections in Massachusetts. For the last three Census cycles, MA has held 9-10…

math.GT2018

You can hear the shape of a billiard table: Symbolic dynamics and rigidity for flat surfaces

Moon Duchin, Viveka Erlandsson, Christopher J. Leininger +1

We give a complete characterization of the relationship between the shape of a Euclidean polygon and the symbolic dynamics of its billiard flow. We prove that the only pairs of tab…

physics.soc-ph2018★ 12 cited

Gerrymandering metrics: How to measure? What's the baseline?

Moon Duchin

This note outlines three intellectually distinct but not mutually exclusive strategies for measuring partisan gerrymandering: partisan symmetry, efficiency gap, and algorithmic sam…

physics.soc-ph2017

A formula goes to court: Partisan gerrymandering and the efficiency gap

Mira Bernstein, Moon Duchin

Recently, a proposal has been advanced to detect unconstitutional partisan gerrymandering with a simple formula called the efficiency gap. The efficiency gap is now working its way…

math.GR2014

A sharper threshold for random groups at density one-half

Moon Duchin, Kasia Jankiewicz, Shelby C. Kilmer +3

In the density model of random groups, we consider presentations with any fixed number m of generators and many random relators of length l, sending l to infinity. If d is a "densi…

math.GR2011

Fine asymptotic geometry in the Heisenberg group

Moon Duchin, Christopher Mooney

For every finite generating set on the integer Heisenberg group H(Z), Pansu showed that the word metric has the large-scale structure of a Carnot-Caratheodory Finsler metric on the…

math.GR2011★ 9 cited

Statistical hyperbolicity in groups

Moon Duchin, Samuel Lelièvre, Christopher Mooney

In this paper, we introduce a geometric statistic called the "sprawl" of a group with respect to a generating set, based on the average distance in the word metric between pairs of…

math.GR2010

The geometry of spheres in free abelian groups

Moon Duchin, Samuel Lelièvre, Christopher Mooney

We study word metrics on Z^d by developing tools that are fine enough to measure dependence on the generating set. We obtain counting and distribution results for the words of leng…

math.GT2005★ 9 cited

Thin triangles and a multiplicative ergodic theorem for Teichmüller geometry

Moon Duchin

We show that, in the Teichmüller metric, "thin-framed triangles are thin"---that is, under suitable hypotheses, the variation of geodesics obeys a hyperbolic-like inequality. This…