English

Another Marcenko-Pastur law for Kendall's tau

Probability 2026-03-20 v3 Spectral Theory

Abstract

Bandeira et al. (2017) show that the eigenvalues of the Kendall correlation matrix of nn i.i.d. random vectors in Rp\mathbb{R}^p are asymptotically distributed like 1/3+(2/3)Yq1/3 + (2/3)Y_q, where YqY_q has a Mar\v{c}enko-Pastur law with parameter q=lim(p/n)q=\lim(p/n) if p,np, n\to\infty proportionately to one another. Here we show that another Mar\v{c}enko-Pastur law emerges in the "ultra-high dimensional" scaling limit where pqn2/2p\sim q'\, n^2/2 for some q>0q'>0: in this quadratic scaling regime, Kendall correlation eigenvalues converge weakly almost surely to (1/3)Yq(1/3)Y_{q'}.

Keywords

Cite

@article{arxiv.2503.18645,
  title  = {Another Marcenko-Pastur law for Kendall's tau},
  author = {Pierre Bousseyroux and Tomas Espana and Matteo Smerlak},
  journal= {arXiv preprint arXiv:2503.18645},
  year   = {2026}
}