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Lecture 10: Reinforcement Learning

<p>May 15, 2015 06:05 PM</p>

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this is Pieeter Abbeel at Cal. &nbsp;CS188;</p>

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how do people and animals learn by reward...</p>

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Agents and Enviro &nbsp;(same as MDP... Markov Decision Proc)</p>

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RL slide</p>

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agent gets feedback in form of reward and ACT so as to maximize rewards.</p>

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all learning base don samples of outcomes</p>

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Agent: &nbsp;Enviro in state S; agent takes action A and gets reward r...</p>

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what is the right thing to do in each state.</p>

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you learn as you go along;</p>

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shows Aibo learning to run</p>

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shows robotic snake &nbsp;(from Andrew Ng) &nbsp;learning to mount step and to side-wind on step.</p>

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toddler robot &nbsp;(auto walks downhill; swinging legs)

motors in ankles... &nbsp;(Seung robot from 2005)

TD learning... figures how to walk &nbsp;&nbsp;(MIT)</p>

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CRAWLER &nbsp;(student project)...</p>

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hip angle and knee angle &nbsp;pulling a block...</p>

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running Q learning...

it gradually learns &nbsp;(it does not know that it's a crawling bot)</p>

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at 10:49 &nbsp;RL &nbsp;still assume an MDP...</p>

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a set of states; a set of actions per state

a model R(s, action, and state prime)

a reward function R</p>

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and T &nbsp;a transition model</p>

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looking for &nbsp;a policy Pi(s)</p>

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see car &nbsp;(go as fast as poss w/o getting overheated);</p>

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context is still MDPs..</p>

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fast and a slow action...</p>

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as an RL learner you don't know that overheated is bad.

must actually try out stuff..</p>

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MDPs are offline!!! &nbsp;(get a model of the world and make a plan then execute it);</p>

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online learning... &nbsp;robot must actually FAIL... don't even know where the failure states are.</p>

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