Upper Bounds on the Average Height of Random Binary Trees

We study the average height of random trees generated by leaf-centric binary tree sources as introduced by Zhang, Yang and Kieffer. A leaf-centric binary tree source induces for every $n\ge 2$ a probability distribution on the set of binary trees with $n$ leaves. Our results generalize a result by Devroye, according to which the average height of a random binary search tree of size $n$ is in $\mathcal{O}(\log n)$.