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arXiv · 2104.08136

Approximating the Earth Mover's Distance between sets of geometric objects

Marc van Kreveld·Frank Staals·Amir Vaxman·Jordi Vermeulen
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Abstract

Given two distributions $P$ and $S$ of equal total mass, the Earth Mover's Distance measures the cost of transforming one distribution into the other, where the cost of moving a unit of mass is equal to the distance over which it is moved. We give approximation algorithms for the Earth Mover's Distance between various sets of geometric objects. We give a $(1 + \varepsilon)$-approximation when $P$ is a set of weighted points and $S$ is a set of line segments, triangles or $d$-dimensional simplices. When $P$ and $S$ are both sets of line segments, sets of triangles or sets of simplices, we give a $(1 + \varepsilon)$-approximation with a small additive term. All algorithms run in time polynomial in the size of $P$ and $S$, and actually calculate the transport plan (that is, a specification of how to move the mass), rather than just the cost. To our knowledge, these are the first combinatorial algorithms with a provable approximation ratio for the Earth Mover's Distance when the objects are continuous rather than discrete points.

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Marc van Kreveld, Frank Staals, Amir Vaxman, Jordi Vermeulen. 2023-02-17. Approximating the Earth Mover's Distance between sets of geometric objects. https://arxiv.org/abs/2104.08136

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