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arXiv · 2501.02325

Revisiting Compactness for District Plans

Kristopher Tapp
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Abstract

Modern sampling methods create ensembles of district maps that score well on discrete compactness scores, whereas the Polsby-Popper and other shape-based scores remain highly relevant for building fair maps and litigating unfair ones. The aim of this paper is twofold. First, we introduce population-weighted versions of shape-based scores and show a precise sense in which this interpolates between shape-based and discrete scores. Second, we introduce a modification of the ReCom sampling method that produces ensembles of maps with improved shape-based compactness scores.

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Kristopher Tapp. 2025-01-04. Revisiting Compactness for District Plans. https://arxiv.org/abs/2501.02325

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