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  #1  
Old 02-09-2013, 09:27 AM
melipone melipone is offline
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Default Question on Gradient

For gradient descent in Q5-6, is the gradient a vector consisting of the partial derivatives wrt u and the partial derivative wrt v or is it the derivative wrt to both u and v?
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Old 02-09-2013, 09:57 AM
kartikeya_t@yahoo.com kartikeya_t@yahoo.com is offline
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Default Re: Question on Gradient

It is the former, i.e., a vector whose first component is the partial derivative of E wrt u, and the second component is the partial derivative of E wrt v.
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Old 02-09-2013, 10:56 AM
melipone melipone is offline
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Default Re: Question on Gradient

Got it!
I have another question: Are you supposed to update the value of the point after updating the weights? I don't see that in the algorithm on p. 95.
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Old 02-09-2013, 01:38 PM
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yaser yaser is offline
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Default Re: Question on Gradient

Quote:
Originally Posted by melipone View Post
Got it!
I have another question: Are you supposed to update the value of the point after updating the weights? I don't see that in the algorithm on p. 95.
In this specific problem, the "weights" are u,v, namely the parameters you are optimizing with respect to.
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  #5  
Old 02-09-2013, 03:33 PM
melipone melipone is offline
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Default Re: Question on Gradient

ah, the point (u,v) = (1,1) is the initial weight?
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Old 02-09-2013, 07:22 PM
butterscotch butterscotch is offline
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Default Re: Question on Gradient

you are right!
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