spring 2012. ashutosh saxena - cornell university · spring 2012. ashutosh saxena ashutosh saxena...

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Ashutosh Saxena

CS 4758/6758: Robot Learning Spring 2012. Ashutosh Saxena

Ashutosh Saxena

Goals

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Ashutosh Saxena

Goals encoded as a Cost Function

� Which areas on the road are good?

Ashutosh Saxena

Optimizing cost function: Descent Methods

� General descent algorithm � Generalization to multiple dimensions � Problems of descent methods, possible

improvements. �  Fixes � Local Minima

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Ashutosh Saxena

Gradient Descent

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Ashutosh Saxena

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Ashutosh Saxena

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Ashutosh Saxena

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Ashutosh Saxena

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Ashutosh Saxena

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Ashutosh Saxena

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Ashutosh Saxena

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Ashutosh Saxena

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Ashutosh Saxena

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Ashutosh Saxena

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Solution to step size

� Back-tracking line search.

◦  Step-size = step-size / 2 ◦ Until new function value gets smaller.

Ashutosh Saxena

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Ashutosh Saxena

Ashutosh Saxena

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