MathDB
Miklós Schweitzer 2008, Problem 11

Source: Miklós Schweitzer 2008

July 30, 2016
Miklos Schweitzercollege contestsnormal distributionprobability

Problem Statement

Let ζ1,,ζn\zeta_1, \ldots, \zeta_n be (not necessarily independent) random variables with normal distribution for which Eζj=0E\zeta_j=0 and Eζj21E\zeta_j^2\le 1 for all 1jn1\le j\le n. Prove that E(max1jnζj)2lognE\left( \max_{1\le j\le n} \zeta_j \right)\le\sqrt{2\log n}
(translated by Miklós Maróti)