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nonconvexcard

A one-parameter class with infinite VC dimension

ProofAdvanced⏱ 1 hourLearning Theoryvc dimensioncounterexampleparameter counting

Problem

Show that H={x↦sign⁡sin⁡(ωx):ω>0}\Hcal = \{x\mapsto\sign\sin(\omega x) : \omega>0\} shatters arbitrarily large finite subsets of R\R, hence has infinite VC dimension despite having one real parameter. Conclude that capacity is not parameter count.

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

Hints

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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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