random walk on hypercube
Source: miklos schweitzer 1997 q10
September 28, 2021
probability and statsMiklos Schweitzer
Problem Statement
Assign independent standard normally distributed random variables to the vertices of an n-dimensional cube. Say one vertex is greater than another if the assigned number is greater. Define a random walk on the vertices according to the following rules:
a) the starting point is chosen from all the vertices with equal probability,
b) during our journey, if we reach a vertex such that there are adjacent vertices which have higher values, we choose the next vertex with equal probability,
c) if there is none, we stop.
Prove that
where is the number of steps of the random walk.