Foundations of Reinforcement Learning and Control: Connections and New Perspectives
Views and opinions expressed are those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them.
1 We use the DeepMind Control Suite implementation (Tassa et al. [92], Zakka et al. [102]). The image of the Cheetah has been reproduced with permission from Tassa et al. [92].
2 In the case of adaptive control, they will form the “reference model” that must be adapted based on feedback (see Section 3.1).
3 Note that the definition of is slightly different between the episodic and continuing settings in RL. In the continuing setting, corresponds to the stationary distribution for the policy , with no dependence on . Otherwise, the rest of the gradient remains the same. Because of this similarity, algorithms designed for the episodic setting can often be applied heuristically to the continuing setting, albeit they should account for differences in state weighting. To clarify terminology, the episodic setting corresponds to batch control problems and the continuing setting corresponds to the continuous setting in control. This terminology should not be confused with the fact that in RL the continuous setting usually means the state and/or action are continuous rather than discrete.
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