The semi-random tree process

Abstract

The online semi-random graph process is a one-player game which starts with the empty graph on $n$ vertices. At every round, a player (called Builder) is presented with a vertex $v$ chosen uniformly at random and independently from previous rounds, and constructs an edge of their choice that is incident to $v$. Inspired by recent advances on the semi-random graph process, we define a family of generalized online semi-random models.

We analyse a particular instance that shares similar features with the original semi-random graph process and determine the hitting times of the classical graph properties minimum degree $k$, $k$-connectivity, containment of a perfect matching, a Hamiltonian cycle and an $H$-factor for a fixed graph $H$ possessing an additional tree-like property. Along the way, we derive a few consequences of the famous Aldous-Broder algorithm that may be of independent interest.