LFD Book Forum Signficance Of High Number Of Iterations

#1
09-03-2012, 09:32 PM
 munchkin Member Join Date: Jul 2012 Posts: 38
Signficance Of High Number Of Iterations

In the context of solving the optimization problem exactly what is the significance of a relatively higher number of iterations prior to returning an alpha vector? Does this mean that the data set is ill-conditioned in some way for the given C value? The iteration count varies widely during each of the runs for the cross validation. Thanks for your attention.
#2
09-06-2012, 04:29 PM
 htlin NTU Join Date: Aug 2009 Location: Taipei, Taiwan Posts: 601
Re: Signficance Of High Number Of Iterations

Quote:
 Originally Posted by munchkin In the context of solving the optimization problem exactly what is the significance of a relatively higher number of iterations prior to returning an alpha vector? Does this mean that the data set is ill-conditioned in some way for the given C value? The iteration count varies widely during each of the runs for the cross validation. Thanks for your attention.
Yes, it means that the data set is ill-conditioned. Usually the physical meaning is that the rank of is not enough (making it hard to separate the examples) and is too large (insisting on separating). Hope this helps.
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#3
09-09-2012, 03:25 PM
 munchkin Member Join Date: Jul 2012 Posts: 38
Re: Signficance Of High Number Of Iterations

Yes. That is very helpful. Thanks!

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