arXiv Statistics ML

Optimal distribution-free sequential change detection with conformal martingales

arXiv Machine Learning
Jun 15

Nonlinear Two-Time-Scale Stochastic Approximation: A Sharp Phase Transition and How to Beat It

arXiv:2606. 14488v1 Announce Type: cross Abstract: Recent finite-time analyses of nonlinear two-time-scale stochastic approximation show that under contractive assumptions the slow iterate $Y_k$ with stepsizes $\beta_k=\Theta(k^{-1})$ and $\alpha_k=\Theta(k^{-a})$, $a\in(1/2,1)$, generally satisfies a mean-square rate of order $k^{-a}$; decoupled $k^{-1}$ rates require strong local linearity.

By Dhruv Sarkar, Vaneet Aggarwal
arXiv Statistics ML
5d ago

A uniform improvement to conformal risk control via a generalization of e-closure

The paper extends the e‑closure principle for multiple testing to general state and action spaces and to arbitrarily indexed risk families. It introduces a recertification method that reallocates unused risk budget, enlarging certifying e‑values while preserving validity and yielding less conservative decisions. Applications include improved conformal risk control and enhanced false discovery rate procedures, with empirical gains shown on CIFAR‑100 and simulations.

By Tian Bai, Aaditya Ramdas
arXiv Machine Learning
Oct 3

Online Generalized-Mean Welfare Maximization: Achieving Near-Optimal Regret from Samples

The paper investigates online fair allocation of sequential items to agents with heterogeneous preferences, aiming to maximize generalized-mean welfare. In an i.i.d. arrival setting, a pure greedy algorithm achieves near-optimal “~O(1/T)” average regret without needing distributional knowledge. For nonstationary arrivals, the authors show that a single historical sample per distribution suffices to recover the same regret rate, using re-solving algorithms that remain robust to distribution shifts.

By Zongjun Yang, Rachitesh Kumar, Christian Kroer
arXiv Machine Learning
Jul 13

Global Sequential Testing for Multi-Stream Auditing

arXiv:2602. 21479v3 Announce Type: replace-cross Abstract: Across many risk-sensitive areas, it is critical to continuously audit machine learning systems as we receive more data to quickly determine if they are performing as designed.

By Beepul Bharti, Ambar Pal, Jeremias Sulam