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Separating the four modes of convergence

ProofIntermediate⏱ 30 minProbabilityconvergencecounterexample

Problem

Construct random variables demonstrating each of the following, and prove your constructions work.

  1. Xn→P0X_n\xrightarrow{\P}0 but not almost surely.
  2. Xn→0X_n\to0 almost surely but not in L1L^1.
  3. Xn⇝XX_n\rightsquigarrow X but XnX_n does not converge to XX in probability.

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

Hints

Hints — 0 of 3 revealed

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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