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VC dimension of halfspaces

ProofIntermediate⏱ 30 minLearning Theoryvc dimensionhalfspaceradon

Problem

Prove that homogeneous halfspaces {x↦sign⁡⟨w,x⟩}\{x\mapsto\sign\langle w,x\rangle\} in Rd\R^d have VC dimension exactly dd, and that with a bias term the dimension is d+1d+1.

Write a complete argument. Every inequality you use should be one you could state precisely.

Solution

Opening this before you have a real attempt on paper is the fastest way to feel like you understand something you cannot reproduce.

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