On Tuesday 04 May 2010, William Stein wrote:
> On Tue, May 4, 2010 at 11:11 AM, William Cauchois <[email protected]> 
wrote:
> > Hi everyone,
> >
> > As part of another project, I completed a rudimentary Python binding
> > to Thorsten Joachims' SVM-Light library (http://
> > svmlight.joachims.org/) implementing a Support Vector Machine. My
> > source code is available at
> >
> > http://bitbucket.org/wcauchois/pysvmlight
> >
> > Are there people doing ML research who would be interested in having
> > access to SVM-Light from inside Sage? Is there anyone who would like
> > to help me get PySVMLight into a more feature-complete state and then
> > integrate it with Sage?
> 
> Could you write a little more to sage-devel about why mathematicians
> might care about "support vector machines" -- it's possible that most
> people reading this have never heard of them.

Since I'm nowhere near an expert, here's the first paragraph from Wikipedia:

"""
Support vector machines (SVMs) are a set of related supervised learning 
methods used for classification and regression. In simple words, given a set 
of training examples, each marked as belonging to one of two categories, an 
SVM training algorithm builds a model that predicts whether a new example 
falls into one category or the other. Intuitively, an SVM model is a 
representation of the examples as points in space, mapped so that the examples 
of the separate categories are divided by a clear gap that is as wide as 
possible. New examples are then mapped into that same space and predicted to 
belong to a category based on which side of the gap they fall on.
"""

http://en.wikipedia.org/wiki/Support_vector_machine

I recently played around with SVM in the context of cryptanalysis to 
distinguish plaintext-ciphertext pairs with certain "good" properties from 
others as part of an attack. For that I actually wrote a little Sage script :) 
I assume SVMs could be useful to classify experimental data etc. in other 
contexts too. 

Btw. I came across SVMs in the context of author identification: you extract 
features such as sentence length and then use those feature vectors to decide 
whether an anonymous text was written by A or B. The idea is that you do not 
need to build a model yourself, the algorithm will attempt to separate your 
training sets as much as possible.

I'd like to see some optional SPKG which provides SVM support. However, in the 
foreseeable future I won't be able to help much since I'm supposed to work on 
my thesis.

Cheers,
Martin

-- 
name: Martin Albrecht
_pgp: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
_otr: 47F43D1A 5D68C36F 468BAEBA 640E8856 D7951CCF
_www: http://www.informatik.uni-bremen.de/~malb
_jab: [email protected]

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