Linear Kernel: Why is it recommended for text classification ?

The Support Vector Machine can be viewed as a kernel machine. As a result, you can change its behavior by using a different kernel function.

The most popular kernel functions are :

  • the linear kernel
  • the polynomial kernel
  • the RBF (Gaussian) kernel
  • the string kernel

The linear kernel is often recommended for text classification

It is interesting to note that :

The original optimal hyperplane algorithm proposed by Vapnik in 1963 was a linear classifier [1]

That's only 30 years later that the kernel trick was introduced.

If it is the simpler algorithm, why is the linear kernel recommended for text classification?

Text is often linearly separable

Most of text classification problems are linearly separable [2]

Linear kernel works well with linearly separable data
Linear kernel works well with linearly separable data

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