activity
20202026
most citedConfidence sequences for sampling without replacement

9 citations · 29 across the 18 of their papers we have counts for

collaborators

19 papers

stat.ME2026

Confidence Horizons

Chase Mathis, Ian Waudby-Smith

Anytime-valid inference enables analysts to continuously monitor their data and stop experiments early. However, the majority of these methods incur a certain conservativeness by r…

cs.LG2026

Post-Training at the Edge of Detectability: A Game-Theoretic Approach to Fine-Tuning

Keegan Harris, Brian W. Lee, Ian Waudby-Smith +3

Reinforcement learning (RL) fine-tuning is widely used in language model training to improve performance on a target task while limiting drift from a reference policy. A standard w…

math.ST2026

Gaffke's confidence interval for the mean of bounded data is inadmissible but asymptotically efficient

Jiahao Ming, Aaditya Ramdas, Yi Shen +2

Given observations , Gaffke (2005) defined \[ K_n(\mathbf x)=\mathbb{P}_{\mathbf D}\!\left\{\sum_{i=1}^n x_iD_i\le 1\right\}, \qquad (D_0,D_1,\ldots,D_n)…

math.ST2026

Post-Hoc Large-Sample Statistical Inference

Ben Chugg, Etienne Gauthier, Michael I. Jordan +2

We derive inferential procedures for large sample sizes that remain valid under data-dependent significance levels (so-called "post-hoc valid inference"). Classical statistical too…

stat.ME2026

Multi-Armed Sequential Hypothesis Testing by Betting

Ricardo J. Sandoval, Ian Waudby-Smith, Michael I. Jordan

We consider a variant of sequential testing by betting where, at each time step, the statistician is presented with multiple data sources (arms) and obtains data by choosing one of…

stat.ME2026

Combining e-values using demi-supermartingales

Jiahao Ming, Aaditya Ramdas, Yi Shen +2

We present a new method for combining e-variables through demi-supermartingales, which settles an old conjecture in the literature on nonparametric mean testing. It also provides a…

stat.ME2026

On Nonasymptotic Confidence Intervals for Treatment Effects in Randomized Experiments

Ricardo J. Sandoval, Sivaraman Balakrishnan, Avi Feller +2

We study nonasymptotic (finite-sample) confidence intervals for treatment effects in randomized experiments. In the existing literature, the effective sample sizes of nonasymptotic…

math.PR2025

Concentration inequalities for strong laws and laws of the iterated logarithm

Johannes Ruf, Ian Waudby-Smith

We derive concentration inequalities for sums of independent and identically distributed random variables that yield non-asymptotic generalizations of several strong laws of large…

math.ST2025

Instance-Log-Optimality of Portfolio-Based E-Processes and their Sequential Hypothesis Tests

Ian Waudby-Smith, Ricardo Sandoval, Ricardo J. Sandoval +1

We consider the problem of sequential hypothesis testing using -processes. For a rich class of composite testing problems---which include bounded mean testing, equal mean testin…

math.PR2025

Nonasymptotic and distribution-uniform Komlós-Major-Tusnády approximation

Ian Waudby-Smith, Martin Larsson, Aaditya Ramdas

We present nonasymptotic concentration inequalities for sums of independent and identically distributed random variables that yield asymptotic strong Gaussian approximations of Kom…

math.PR2024

Distribution-uniform strong laws of large numbers

Ian Waudby-Smith, Martin Larsson, Aaditya Ramdas

We revisit the question of whether the strong law of large numbers (SLLN) holds uniformly in a rich family of distributions, culminating in a distribution-uniform generalization of…

math.ST2023

Distribution-uniform anytime-valid sequential inference and the Robbins-Siegmund distributions

Ian Waudby-Smith, Edward H. Kennedy, Aaditya Ramdas

This paper develops a theory of distribution- and time-uniform asymptotics, culminating in the first large-sample anytime-valid inference procedures that are shown to be uniformly…

stat.AP2023★ 7 cited

Anytime-Valid Confidence Sequences in an Enterprise A/B Testing Platform

Akash V. Maharaj, Ritwik Sinha, David Arbour +7

A/B tests are the gold standard for evaluating digital experiences on the web. However, traditional "fixed-horizon" statistical methods are often incompatible with the needs of mod…

stat.ME2022★ 1 cited

Anytime-valid off-policy inference for contextual bandits

Ian Waudby-Smith, Lili Wu, Aaditya Ramdas +2

Contextual bandit algorithms are ubiquitous tools for active sequential experimentation in healthcare and the tech industry. They involve online learning algorithms that adaptively…

stat.ME2022★ 1 cited

Nonparametric extensions of randomized response for private confidence sets

Ian Waudby-Smith, Zhiwei Steven Wu, Aaditya Ramdas

This work derives methods for performing nonparametric, nonasymptotic statistical inference for population means under the constraint of local differential privacy (LDP). Given bou…

stat.AP2021

RiLACS: Risk-Limiting Audits via Confidence Sequences

Ian Waudby-Smith, Philip B. Stark, Aaditya Ramdas

Accurately determining the outcome of an election is a complex task with many potential sources of error, ranging from software glitches in voting machines to procedural lapses to…

math.ST2021★ 4 cited

Time-uniform central limit theory and asymptotic confidence sequences

Ian Waudby-Smith, David Arbour, Ritwik Sinha +2

Confidence intervals based on the central limit theorem (CLT) are a cornerstone of classical statistics. Despite being only asymptotically valid, they are ubiquitous because they p…

math.ST2020★ 7 cited

Estimating means of bounded random variables by betting

Ian Waudby-Smith, Aaditya Ramdas

This paper derives confidence intervals (CI) and time-uniform confidence sequences (CS) for the classical problem of estimating an unknown mean from bounded observations. We presen…

stat.ME2020★ 9 cited

Confidence sequences for sampling without replacement

Ian Waudby-Smith, Aaditya Ramdas

Many practical tasks involve sampling sequentially without replacement (WoR) from a finite population of size , in an attempt to estimate some parameter . Accurately qu…