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Old 12-18-2015, 04:26 AM
henry2015 henry2015 is offline
Join Date: Aug 2015
Posts: 31
Default Problem 1.3 c

= ||w(t-1) + y(t-1)x(t-1)||^2 <--- this is from the PLA iteration
<=(||w(t-1)|| + ||y(t-1)x(t-1)||)^2 <--- a property: ||a + b|| <= ||a|| + ||b||
= ||w(t-1)||^2 + 2y(t-1)||w(t-1)||||x(t-1)|| + y(t-1)^2||x(t-1)||^2
= ||w(t-1)||^2 + 2y(t-1)||w(t-1)||||x(t-1)|| + ||x(t-1)||^2

Now, it seems like 2y(t-1)||w(t-1)||||x(t-1)|| is somehow <= 0.

||w(t-1)||||x(t-1)|| is >= 0 tho.

hence, it seems like 2y(t-1) is somehow <= 0.

It seems like I am on the wrong track as I am not using the hint mentioned in the question at all.

Any pointer?

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