English

A family of divergence-based correlation measures for contingency tables under bivariate normality

Methodology 2026-04-16 v2

Abstract

We propose a family of association measures for two-way contingency tables whose latent distribution can be assumed to be bivariate normal. When this assumption holds, the power-divergence measuring departure from independence can be approximated in closed form as a function of the latent correlation coefficient. By inverting this relationship, we obtain a family of measures ρ(λ)\rho_{(\lambda)}, indexed by a scalar parameter 1λ1-1 \leq \lambda \leq 1, that directly approximates the latent correlation. Special cases include the informational measure of correlation proposed by Linfoot (1957) at λ=0\lambda = 0 and Pearson's contingency coefficient CC at λ=1\lambda = 1. Additionally, we derive asymptotic distributions via the delta method and construct two families of confidence intervals. Simulation studies confirm that the proposed measures approximate the true latent correlation more faithfully than conventional divergence-based measures, and that they successfully distinguish between weak and moderate associations where existing measures tend to give indistinguishable values. Compared with the polychoric correlation coefficient, the proposed measures are computed several thousand times faster and remain numerically stable even when the latent correlation is close to one.

Keywords

Cite

@article{arxiv.2603.13848,
  title  = {A family of divergence-based correlation measures for contingency tables under bivariate normality},
  author = {Wataru Urasaki},
  journal= {arXiv preprint arXiv:2603.13848},
  year   = {2026}
}