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Where is it best to use svm with linear kernel?

I am currently studing svm and was wondering what the application of svm`s with linear kernel is. In my opinion it must be something applied to solving a linear optimization problem. Is this correct?

I appreciate your answer!

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Carol.Kar Avatar asked Dec 13 '13 12:12

Carol.Kar


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2 Answers

One more thing to add: linear SVM is less prone to overfitting than non-linear. And you need to decide which kernel to choose based on your situation: if your number of features is really large compared to the training sample, just use linear kernel; if your number of features is small, but the training sample is large, you may also need linear kernel but try to add more features; if your feature number is small (10^0 - 10^3), and the sample number is intermediate (10^1 - 10^4), use Gaussian kernel will be better.

As far as I know, SVM with linear kernel is usually comparable with logistic regression .

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lennon310 Avatar answered Oct 16 '22 09:10

lennon310


Linear kernel has some advantages but probably (in my opinion) the most significant one is the fact that generally is way faster to train in comparison with non-linear kernels such as RBF.

If your dataset size is in terms of gigabytes, you would see that the training time difference is huge (minutes vs. hours).

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Pedrom Avatar answered Oct 16 '22 10:10

Pedrom