no code implementations • 29 Mar 2024 • Andrew Bennett, Nathan Kallus, Miruna Oprescu, Wen Sun, Kaiwen Wang
We characterize the sharp bounds on policy value under this model, that is, the tightest possible bounds given by the transition observations from the original MDP, and we study the estimation of these bounds from such transition observations.
no code implementations • 6 Nov 2023 • Andrew Bennett, Nathan Kallus, Miruna Oprescu
Low-Rank Markov Decision Processes (MDPs) have recently emerged as a promising framework within the domain of reinforcement learning (RL), as they allow for provably approximately correct (PAC) learning guarantees while also incorporating ML algorithms for representation learning.
no code implementations • 25 Jul 2023 • Andrew Bennett, Nathan Kallus, Xiaojie Mao, Whitney Newey, Vasilis Syrgkanis, Masatoshi Uehara
We consider estimation of parameters defined as linear functionals of solutions to linear inverse problems.
no code implementations • 10 Feb 2023 • Andrew Bennett, Nathan Kallus, Xiaojie Mao, Whitney Newey, Vasilis Syrgkanis, Masatoshi Uehara
In this paper, we study nonparametric estimation of instrumental variable (IV) regressions.
1 code implementation • 26 Oct 2022 • Andrew Bennett, Dipendra Misra, Nathan Kallus
Many existing approaches to safe RL rely on receiving numeric safety feedback, but in many cases this feedback can only take binary values; that is, whether an action in a given state is safe or unsafe.
no code implementations • 17 Aug 2022 • Andrew Bennett, Nathan Kallus, Xiaojie Mao, Whitney Newey, Vasilis Syrgkanis, Masatoshi Uehara
In a variety of applications, including nonparametric instrumental variable (NPIV) analysis, proximal causal inference under unmeasured confounding, and missing-not-at-random data with shadow variables, we are interested in inference on a continuous linear functional (e. g., average causal effects) of nuisance function (e. g., NPIV regression) defined by conditional moment restrictions.
1 code implementation • NeurIPS 2023 • Masatoshi Uehara, Haruka Kiyohara, Andrew Bennett, Victor Chernozhukov, Nan Jiang, Nathan Kallus, Chengchun Shi, Wen Sun
Finally, we extend our methods to learning of dynamics and establish the connection between our approach and the well-known spectral learning methods in POMDPs.
1 code implementation • 28 Oct 2021 • Andrew Bennett, Nathan Kallus
To answer these, we extend the framework of proximal causal inference to our POMDP setting, providing a variety of settings where identification is made possible by the existence of so-called bridge functions.
no code implementations • 21 May 2021 • Andrew Bennett, Dipendra Misra, Nga Than
Topic models are widely used in studying social phenomena.
2 code implementations • 17 Dec 2020 • Andrew Bennett, Nathan Kallus
The conditional moment problem is a powerful formulation for describing structural causal parameters in terms of observables, a prominent example being instrumental variable regression.
no code implementations • 27 Jul 2020 • Andrew Bennett, Nathan Kallus, Lihong Li, Ali Mousavi
We study an OPE problem in an infinite-horizon, ergodic Markov decision process with unobserved confounders, where states and actions can act as proxies for the unobserved confounders.
1 code implementation • ICML 2020 • Andrew Bennett, Nathan Kallus
We show that, under a correct specification assumption, the weighted classification formulation need not be efficient for policy parameters.
1 code implementation • NeurIPS 2019 • Andrew Bennett, Nathan Kallus
We study the question of policy evaluation when we instead have proxies for the latent confounders and develop an importance weighting method that avoids fitting a latent outcome regression model.
2 code implementations • NeurIPS 2019 • Andrew Bennett, Nathan Kallus, Tobias Schnabel
Instrumental variable analysis is a powerful tool for estimating causal effects when randomization or full control of confounders is not possible.
no code implementations • WS 2018 • Steven Xu, Andrew Bennett, Doris Hoogeveen, Jey Han Lau, Timothy Baldwin
Community question answering (cQA) forums provide a rich source of data for facilitating non-factoid question answering over many technical domains.
5 code implementations • EMNLP 2018 • Dipendra Misra, Andrew Bennett, Valts Blukis, Eyvind Niklasson, Max Shatkhin, Yoav Artzi
We propose to decompose instruction execution to goal prediction and action generation.
1 code implementation • 31 May 2018 • Valts Blukis, Nataly Brukhim, Andrew Bennett, Ross A. Knepper, Yoav Artzi
We introduce a method for following high-level navigation instructions by mapping directly from images, instructions and pose estimates to continuous low-level velocity commands for real-time control.