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What is the dual form of SVM?

Updated May 17, 2026

Short answer

The dual form expresses SVM optimization in terms of Lagrange multipliers and support vectors.

Deep explanation

Instead of solving primal optimization directly, dual formulation allows use of kernels and depends only on dot products of inputs, making high-dimensional computation feasible.

Real-world example

Used in NLP classification with high-dimensional sparse vectors.

Common mistakes

  • Ignoring that kernels rely on dual form.

Follow-up questions

  • Why use dual form?
  • When is primal preferred?

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