Timezone: »
Standard reinforcement learning (RL) aims to find an optimal policy that identifies the best action for each state. However, in healthcare settings, many actions may be near-equivalent with respect to the reward (e.g., survival). We consider an alternative objective -- learning set-valued policies to capture near-equivalent actions that lead to similar cumulative rewards. We propose a model-free algorithm based on temporal difference learning and a near-greedy heuristic for action selection. We analyze the theoretical properties of the proposed algorithm, providing optimality guarantees and demonstrate our approach on simulated environments and a real clinical task. Empirically, the proposed algorithm exhibits good convergence properties and discovers meaningful near-equivalent actions. Our work provides theoretical, as well as practical, foundations for clinician/human-in-the-loop decision making, in which humans (e.g., clinicians, patients) can incorporate additional knowledge (e.g., side effects, patient preference) when selecting among near-equivalent actions.
Author Information
Shengpu Tang (University of Michigan)

Shengpu Tang is a PhD candidate in the computer science department at the University of Michigan. He is a member of the Machine Learning for Data-Driven Decisions (MLD3) research group led by Jenna Wiens. His current research focuses on developing computational methods that help solve important problems in healthcare, such as risk stratification and dynamic treatment recommendations. More generally, he is interested in broader applications of AI/ML, reinforcement learning and graph mining, computer game design, self-driving cars, security and hacking, as well as teaching. For more details, see his website at https://shengpu-tang.me/
Aditya Modi (University of Michigan)
Michael Sjoding (University of Michigan)
Jenna Wiens (University of Michigan)
More from the Same Authors
-
2021 : Model Selection for Offline Reinforcement Learning: Practical Considerations for Healthcare Settings »
Shengpu Tang · Jenna Wiens -
2022 : Big Control Actions Help Multitask Learning of Unstable Linear Systems »
Aditya Modi · Ziping Xu · Mohamad Kazem Shirani Faradonbeh · Ambuj Tewari -
2022 : Leveraging Factored Action Spaces for Efficient Offline Reinforcement Learning in Healthcare »
Shengpu Tang · Maggie Makar · Michael Sjoding · Finale Doshi-Velez · Jenna Wiens -
2023 : Leveraging Factored Action Spaces for Off-Policy Evaluation »
Aaman Rebello · Shengpu Tang · Jenna Wiens · Sonali Parbhoo -
2023 : Leveraging Factored Action Spaces for Off-Policy Evaluation »
Aaman Rebello · Shengpu Tang · Jenna Wiens · Sonali Parbhoo -
2019 : posters »
Zhengxing Chen · Juan Jose Garau Luis · Ignacio Albert Smet · Aditya Modi · Sabina Tomkins · Riley Simmons-Edler · Hongzi Mao · Alexander Irpan · Hao Lu · Rose Wang · Subhojyoti Mukherjee · Aniruddh Raghu · Syed Arbab Mohd Shihab · Byung Hoon Ahn · Rasool Fakoor · Pratik Chaudhari · Elena Smirnova · Min-hwan Oh · Xiaocheng Tang · Tony Qin · Qingyang Li · Marc Brittain · Ian Fox · Supratik Paul · Xiaofeng Gao · Yinlam Chow · Gabriel Dulac-Arnold · Ofir Nachum · Nikos Karampatziakis · Bharathan Balaji · Supratik Paul · Ali Davody · Djallel Bouneffouf · Himanshu Sahni · Soo Kim · Andrey Kolobov · Alexander Amini · Yao Liu · Xinshi Chen · · Craig Boutilier