OAASVM

Multi-class SVM using One-Agains-All decomposition.


 
 Synopsis:
  model = oaasvm( data )
  model = oaasvm( data, options)

 Description:
  model = oaasvm( data ) uses one-agains-all deconposition
   to train the multi-class Support Vector Machines (SVM)
   classifier. The classification into nclass classes 
   is decomposed to nclass binary problems.

  model = oaasvm( data, options) allows to specify the
   binary SVM solver and its paramaters.

 Input:
  data [struct] Training data:
   .X [dim x num_data] Training vectors.
   .y [1 x num_data] Labels of training data (1,2,...,nclass). 

  options [struct] Control parameters:
   .bin_svm [string] Function which implements the binary SVM 
     solver; (default 'smo').
   .verb [1x1] If 1 then a progress info is displayed (default 0).
  The other fileds of options specifies the options of the binary
  solver (e.g., ker, arg, C). See help of the selected solver.
  
 Output:
  model [struct] Multi-class SVM classifier:
   .Alpha [nsv x nclass] Weights (Lagrangians).
   .b [nclass x 1] Biases of discriminant functions.
   .sv.X [dim x nsv] Support vectors.
   .nsv [1x1] Number of support vectors.
   .trnerr [1x1] Training error.
   .kercnt [1x1] Number of kernel evaluations.
   .options [struct[ Copy of input argument options.

 Example:
  data = load('pentagon');
  options = struct('ker','rbf','arg',1,'C',10,'verb',1);
  model = oaasvm(data,options);
  figure; 
  ppatterns(data); ppatterns( model.sv.X, 'ok',13);
  pboundary( model );

 See also
  SVMCLASSOAOSVM.


Source: oaasvm.m

About: Statistical Pattern Recognition Toolbox
(C) 1999-2005, Written by Vojtech Franc and Vaclav Hlavac
Czech Technical University Prague
Faculty of Electrical Engineering
Center for Machine Perception

Modifications:
25-jan-2005, VF, option solver replaced by bin_svm
27-may-2004, VF, completely re-programed
18-sep-2001, V. Franc, created