arXiv Machine Learning

Minimax Rates for Estimating Powered Sliced Wasserstein Functionals

arXiv:2610. 12740v1 Announce Type: cross Abstract: We study the two-sample estimation of the powered Sliced Wasserstein functional under projected $r$-th moment assumptions.

arXiv Machine Learning
6d ago

Near Minimax Rate for Quantile Distributional Reinforcement Learning

The paper investigates quantile distributional policy evaluation by approximating the return distribution under a policy with a quantile Bellman fixed point. It constructs an estimator from an empirical Markov decision process and derives non‑asymptotic error bounds in Wasserstein distances, achieving root‑n rates that are independent of the quantile resolution for a wide range of Wasserstein orders. The authors also characterize the exact local asymptotic minimax risk and show that their estimator attains this optimal rate, while examining how the risk depends on resolution in simple state‑space examples.

By Zijie Cheng, Zhihua Zhang
arXiv Statistics ML
Oct 9

Estimation of the sub-Gaussian Parameter

arXiv:2606. 06384v2 Announce Type: replace-cross Abstract: The sub-Gaussian parameter (also called the variance proxy) of a mean-zero random variable $X$ is defined as $\xi^2_\star = \sup_{\lambda \in \mathbb{R}} L(\lambda)$ where $L(\lambda) = \frac{2}{\lambda^2} \log \mathbb{E} e^{\lambda X}$ is a weighted cumulant generating function.

By Jason Liu, Min Xu, Jinchuan Xing
arXiv AI
Jun 8

A Temporal Spatial Minimax Rate for Smoothly-Varying Distributions in Wasserstein Space

arXiv:2606. 07325v1 Announce Type: cross Abstract: We study the minimax rate of estimating a future value $\mu_{t_n+h}$ of a curve $t\mapsto\mu_t$ in the $2$-Wasserstein space $\mathcal{P}_2(\mathbb{R}^d)$ from finitely many noisy snapshots of its past, under an adiabatic bound $\|\nabla_t^k v\|\le\varepsilon$ on the $k$-th covariant derivative of the velocity field.

By Munsik Kim
arXiv Statistics ML
1d ago

Wasserstein-Cram\'er-Rao Theory of Unbiased Estimation

arXiv:2511.07414v2 Announce Type: replace-cross Abstract: The quantity of interest in the classical Cram\'er-Rao theory of unbiased estimation (e.g., the Cram\'er-Rao lower bound, its exact attainmen...

By Nicol\'as Garc\'ia Trillos, Adam Quinn Jaffe, Bodhisattva Sen
arXiv Machine Learning
Oct 15

From Global to Tail Convergence: Dynamics of $\alpha$-Stable Score-Based Generative Models

arXiv:2610. 19773v1 Announce Type: new Abstract: Score-based generative models driven by $\alpha$-stable L{\'e}vy processes have been proposed as an alternative to Brownian diffusion models, with empirical evidence suggesting improved sampling and better modeling of heavy-tailed data.

By Ianis Hammani (ENS Paris Saclay, LMO), Claire Boyer (LMO, IUF)
arXiv Machine Learning
Sep 30

Learning Distributionally Robust First-Order Methods for Convex Optimization

The paper introduces a distributionally robust method for learning hyperparameters of first‑order convex optimization algorithms. By minimizing a Wasserstein‑robust performance estimation problem over a dataset of problem instances, the approach interpolates between classical learning‑to‑optimize (L2O) and worst‑case PEP design. The authors solve the resulting problem with stochastic gradient descent, provide high‑probability risk bounds, and demonstrate that the learned algorithms outperform both worst‑case optimal and vanilla L2O baselines on logistic regression, LASSO, and linear programming tasks.

By Vinit Ranjan, Jisun Park, Bartolomeo Stellato