no code implementations • 29 Nov 2022 • Chinmaya Kausik, Yangyi Lu, Kevin Tan, Maggie Makar, Yixin Wang, Ambuj Tewari
Evaluating and optimizing policies in the presence of unobserved confounders is a problem of growing interest in offline reinforcement learning.
no code implementations • 10 Aug 2021 • Yangyi Lu, Ziping Xu, Ambuj Tewari
However, the modern precision medicine movement has been enabled by a confluence of events: scientific advances in fields such as genetics and pharmacology, technological advances in mobile devices and wearable sensors, and methodological advances in computing and data sciences.
no code implementations • NeurIPS 2021 • Yangyi Lu, Amirhossein Meisami, Ambuj Tewari
In causal bandit problems, the action set consists of interventions on variables of a causal graph.
no code implementations • 15 Feb 2021 • Yangyi Lu, Amirhossein Meisami, Ambuj Tewari
We introduce causal Markov Decision Processes (C-MDPs), a new formalism for sequential decision making which combines the standard MDP formulation with causal structures over state transition and reward functions.
no code implementations • 4 Jun 2020 • Yangyi Lu, Amirhossein Meisami, Ambuj Tewari
To get around the computational intractability of covering based approaches, we propose an efficient algorithm by extending the "Explore-Subspace-Then-Refine" algorithm of~\citet{jun2019bilinear}.
no code implementations • 11 Oct 2019 • Yangyi Lu, Amirhossein Meisami, Ambuj Tewari, Zhenyu Yan
For example, we observe that even with a few hundreds of iterations, the regret of causal algorithms is less than that of standard algorithms by a factor of three.
no code implementations • 28 Jun 2017 • Huitian Lei, Yangyi Lu, Ambuj Tewari, Susan A. Murphy
Increasing technological sophistication and widespread use of smartphones and wearable devices provide opportunities for innovative and highly personalized health interventions.