Finite Gelfand Pair Approaches for Ehrenfest Diffusion Model

A classical diffusion model of Ehrenfest which consists of $2$-urns and $n$-balls is realized by a finite Gelfand pair $(H_{n},S_{n})$, where $H_{n}$ is the hyperoctahedral group and $S_{n}$ is the symmetric group. This fact can be generalized to multi-urn version by using Gelfand pairs of complex reflection groups.