ResearchResearch paperReinforcement Learning1 source · Oct 20, 2026

Confessions of a Masked MDP

In reinforcement learning, one presumes the action set to be known ahead of time, and, thus, one must know if any state-action pairs are not permissible

Key points

  • properties, we study how to combine the search for an optimal policy with the learning of the mask itself, under a linear MDP model in which each attempted
  • optimistic optimization and show that it is minimax optimal, which we show is also computationally efficient.
  • We propose an alternative, which is also computationally efficient, which plans its exploration strategy.
  • formal interpretation as an analogue of information-directed-sampling for deterministic feedback, which may be of independent interest.

Sources (1)

  • [1]Confessions of a Masked MDP
    arXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 20, 03:22 PM
    In reinforcement learning, one presumes the action set to be known ahead of time, and, thus, one must know if any state-action pairs are not permissible
    properties, we study how to combine the search for an optimal policy with the learning of the mask itself, under a linear MDP model in which each attempted

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