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nonconvexcard

The information matrix equality

ProofGraduate⏱ 1 hourFine-Tuningfisherhessianregularitymisspecification

Problem

  1. Prove F(θ)=−Epθ[∇2log⁡pθ]F(\theta) = -\E_{p_\theta}[\nabla^2\log p_\theta], stating where each regularity condition is used.
  2. Give an example where the conclusion fails because the support depends on θ\theta.
  3. Explain what changes when the expectation is taken under a data distribution different from pθp_\theta, and name the resulting correction.

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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