collaborators

20 papers

cs.DS2026

Exact simulation of diffusions and improved algorithms for log-concave sampling

Fan Chen, Sinho Chewi, Alexander Rakhlin +1

We study exact simulation of diffusions via rejection sampling on path space using unbiased estimators of the density ratio obtained from Girsanov's theorem. When applied to the un…

cs.LG2026

End-to-End Efficient RL for Linear Bellman Complete MDPs with Deterministic Transitions

Zakaria Mhammedi, Alexander Rakhlin, Nneka Okolo

We study reinforcement learning (RL) with linear function approximation in Markov Decision Processes (MDPs) satisfying \emph{linear Bellman completeness} -- a fundamental setting w…

math.ST2026

Demonstration Experiments

Guido Imbens, Lorenzo Masoero, Alexander Rakhlin +2

Adaptive experiments are used extensively in online platforms, healthcare and biotechnology, and the social sciences. Often, the primary goal is not to precisely estimate a treatme…

cs.LG2026

Learning with Simulators: No Regret in a Computationally Bounded World

Sasha Voitovych, Abhishek Shetty, Noah Golowich +1

Understanding the minimal assumptions necessary for generalization is the fundamental question in learning theory. Unfortunately, most results rely heavily on independence (or some…

cs.LG2026

The Sample Complexity of Multiclass and Sparse Contextual Bandits

Liad Erez, Fan Chen, Alon Cohen +4

We study contextual bandits in the stochastic i.i.d.\ setting, where a learner observes contexts drawn from an unknown distribution, selects actions from a finite set , and aims…

math.ST2026

High-accuracy log-concave sampling with stochastic queries

Fan Chen, Sinho Chewi, Constantinos Daskalakis +1

We show that high-accuracy guarantees for log-concave sampling -- that is, iteration and query complexities which scale as , where is the desired targ…