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arXiv · 2007.04462

Scalable Computations of Wasserstein Barycenter via Input Convex Neural Networks

Jiaojiao Fan·Amirhossein Taghvaei·Yongxin Chen
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Abstract

Wasserstein Barycenter is a principled approach to represent the weighted mean of a given set of probability distributions, utilizing the geometry induced by optimal transport. In this work, we present a novel scalable algorithm to approximate the Wasserstein Barycenters aiming at high-dimensional applications in machine learning. Our proposed algorithm is based on the Kantorovich dual formulation of the Wasserstein-2 distance as well as a recent neural network architecture, input convex neural network, that is known to parametrize convex functions. The distinguishing features of our method are: i) it only requires samples from the marginal distributions; ii) unlike the existing approaches, it represents the Barycenter with a generative model and can thus generate infinite samples from the barycenter without querying the marginal distributions; iii) it works similar to Generative Adversarial Model in one marginal case. We demonstrate the efficacy of our algorithm by comparing it with the state-of-art methods in multiple experiments.

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Jiaojiao Fan, Amirhossein Taghvaei, Yongxin Chen. 2021-11-27. Scalable Computations of Wasserstein Barycenter via Input Convex Neural Networks. https://arxiv.org/abs/2007.04462

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