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Old 05-22-2013, 12:48 PM
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yaser yaser is offline
Join Date: Aug 2009
Location: Pasadena, California, USA
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Default Re: Q1 Quadratic Programming

Originally Posted by alasdairj View Post
the original problem for hard-margin SVM seems like a "quadratic programming" problem - so my real question is this: why do we do the "dual" mapping to get the problem stated in terms of alpha? Is this purely to get it into a more convenient form for QP packages? I am missing something, but I don't know what :-).
The number of variables in the original problem depends on the dimensionality of the weight space, whereas the number of variables in the dual problem does not. This makes a difference if that dimensionality is high, which is often the case in nonlinear transforms.
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