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Well, there is an answer here <http://www.mathworks.com/matlabcentral/answers/64475-does-anybody-have-expertise-with-matlab-svm...

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Answered 2 years ago

Check the |ConvergenceInfo.Converged| property of the returned object to see if optimization converged. This behavior of |fit...

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Answered 5 months ago

1. You can report anything you like as long as you report an estimate obtained by cross-validation or using an independent test ...

See my comments at the bottom of this thread <http://www.mathworks.com/matlabcentral/answers/62757-how-do-i-find-slack-variables...

Answered 3 years ago

I described approaches for learning on imbalanced data here <http://www.mathworks.com/matlabcentral/answers/11549-leraning-class...

This is a difficult problem for SVM. SVM performs best when two classes are separable or have a modest overlap. This is not the ...

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Answered 29 days ago

Look at the doc/help for |fitcsvm| or, alternatively look at the |ConvergenceInfo| property in the returned object. There are se...

Binary SVM models trained by ECOC are saved in the BinaryLearners property, which is a cell array. You can't change the Sigma pr...

|multisvm| appears to be built on top of the older, slower |svmtrain| function, while |fitcecoc| uses the newer, faster C++ impl...

Replace temp = zeros(length(mu),1); for i = 1:length(mu) temp(i) = normrnd(mu(i),sigma(i)); end with ...

Answered 1 year ago

For 3 neighbors, the posterior probability has at most 4 distinct values, namely (0:3)/3. Likely less for the Fisher iris data b...

The MATLAB implementation is based on this book: Breiman, L., J. Friedman, R. Olshen, and C. Stone. Classification and Regres...

I am not an expert in image analysis, but it seems you misunderstand what you need to do. LDA uses matrix X in which rows are ob...

I described strategies for learning on imbalanced data in this post http://www.mathworks.com/matlabcentral/answers/11549-leranin...

You might want to start here http://en.wikipedia.org/wiki/One-class_classification The 1st reference (PhD thesis) gives an overv...

You are missing my point about the majority class. Let me try again. Suppose you generate 200 observations and assign labels ...

Combining two objects would be hard. You can work around this by growing one big ensemble and treating parts of it as separate e...

The answer depends on how you define a "fair" classifier. If the ultimate goal of your analysis is to minimize the overall class...

Answered 4 years ago

The prediction of a regression tree is the mean of observed responses over observations landing on this node. If you passed in o...

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Answered 1 month ago

This likely means that some variables in the new data have values well outside their ranges in the training data. Think about wh...

Answered 3 months ago

You need to read the whole section and the one that follows, Computing the support vector classifier. If you, you will notice th...

Just convert your cell array into a matrix. Yes, dummy variables will lose their identity in the sense that different levels of ...

Answered 4 months ago

_So, my question is: does Matlab update the the priors and reset the cost function to the default as an equivalent operation to ...

In 14a and 14b, the Beta coefficients of an SVM model need to be divided by KernelParameters.Scale to get correct predictions. I...

|fitcsvm| passes class prior probabilities found *from the entire data* into each fold. Look at |CVSVMModel.Trained{1}.Prior|, |...

The error message says "You must pass scores as a vector..." You are passing it as a matrix with two columns. How would |perfcur...

Answered 6 months ago

This should work: function depth = treedepth(tree) parent = tree.Parent; depth = 0; node = parent(end); ...

Answered 7 months ago

The error says that 1 is not found in t2. Note that your |groups| variable is logical, and so are |t1| and |t2|, but 1 is double...

ClassificationTree is based on Breiman, L., J. Friedman, R. Olshen, and C. Stone, Classification and Regression Trees, and uses ...

Use a loop: for n=1:30 view(t.Trees{n}); end

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