Multi-Class SVM( one versus all)

 I know that LIBSVM only allows one-vs-one classification when it comes to multi-class SVM. However, I would like to tweak it a bit to perform one-against-all classification. I have tried to perform one-against-all below. Is this the correct approach? 

The code: 

 

TrainLabel;TrainVec;TestVec;TestLaBel;
u=unique(TrainLabel);
N=length(u);
if(N>2)
    itr=1;
    classes=0;
    while((classes~=1)&&(itr<=length(u)))
        c1=(TrainLabel==u(itr));
        newClass=c1;
        model = svmtrain(TrainLabel, TrainVec, '-c 1 -g 0.00154'); 
        [predict_label, accuracy, dec_values] = svmpredict(TestLabel, TestVec, model);
        itr=itr+1;
    end
itr=itr-1;
end 

I might have done some mistakes. I would like to hear some feedback. Thanks.

Second Part: As grapeot said : I need to do Sum-pooling (or voting as a simplified solution) to come up with the final answer. I am not sure how to do it. I need some help on it; I saw the python file but still not very sure. I need some help.  

NOTE:-


Matlabsolutions.com provide latest MatLab Homework Help,MatLab Assignment Help , Finance Assignment Help for students, engineers and researchers in Multiple Branches like ECE, EEE, CSE, Mechanical, Civil with 100% output.Matlab Code for B.E, B.Tech,M.E,M.Tech, Ph.D. Scholars with 100% privacy guaranteed. Get MATLAB projects with source code for your learning and research.    

Answers: 

 

 %# Fisher Iris dataset
load fisheriris
[~,~,labels] = unique(species);   %# labels: 1/2/3
data = zscore(meas);              %# scale features
numInst = size(data,1);
numLabels = max(labels);

%# split training/testing
idx = randperm(numInst);
numTrain = 100; numTest = numInst - numTrain;
trainData = data(idx(1:numTrain),:);  testData = data(idx(numTrain+1:end),:);
trainLabel = labels(idx(1:numTrain)); testLabel = labels(idx(numTrain+1:end));
%# train one-against-all models
model = cell(numLabels,1);
for k=1:numLabels
    model{k} = svmtrain(double(trainLabel==k), trainData, '-c 1 -g 0.2 -b 1');
end
 

Comments

Popular posts from this blog

Why do I get a "Too many input arguments" error when not passing any?

Why Red, Green, Blue channels of image separetely are grayscaled (Matlab)?

How is full convolution performed using MATLAB's conv2 function?