https://classroom.udacity.com/courses/ud501/lessons/5326212698/concepts/54629888620923

hallucinate 产生幻觉

Dyna-Q：混合 Model-Free 和 Model-based

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每一次和真实世界的交互，都会自己更新100次。

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T'[s,a,s']: 从状态 s，采取动作 a，到状态 s’的概率
R'[s,a]: 从状态 s，采取动作 a的 reward

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根据真实世界发生的次数，更新 T

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练习: How To Evaluate T?

Type in your expression usingMathQuill

• a WYSIWYG math renderer that understands LaTeX.

Correction: The expression should be:

Computing transition probabilities using counts image.png image.png image.png

R：模型中的 Reward
r: 真实的立即 reward

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Summary

The Dyna architecture consists of a combination of:

• direct reinforcement learning from real experience tuples gathered by acting in an environment,
• updating an internal model of the environment, and,
• using the model to simulate experiences.

Sutton and Barto.
Reinforcement Learning: An Introduction. MIT Press, Cambridge, MA, 1998. [web]

Resources

• Richard S. Sutton. Integrated architectures for learning, planning, and reacting based on approximating dynamic programming. In

  Proceedings of the Seventh International Conference on Machine Learning, Austin, TX, 1990. [pdf]

• Sutton and Barto.

  Reinforcement Learning: An Introduction. MIT Press, Cambridge, MA, 1998. [web]

• RL course by David Silver

  (videos, slides)

  • Lecture 8: Integrating Learning and Planning [pdf]