On Rank Correlation Coefficients

Alexei Stepanov

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arXiv · 2506.06056

On Rank Correlation Coefficients

Alexei Stepanov

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Abstract

In the present paper, we propose a new rank correlation coefficient $r_n$, which is a sample analogue of the theoretical correlation coefficient $r$, which, in turn, was proposed in the recent work of Stepanov (2025b). We discuss the properties of $r_n$ and compare $r_n$ with known rank Spearman $\rho_{S,n}$, Kendall $\tau_n$ and sample Pearson $\rho_n$ correlation coefficients. Simulation experiments show that when the relationship between $X$ and $Y$ is not close to linear, $r_n$ performs better than other correlation coefficients. We also find analytically the values of $Var(\tau_n)$ and $Var(r_n)$. This allows to estimate theoretically the asymptotic performance of $\tau_n$ and $r_n$.

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BibTeX RIS

Alexei Stepanov. 2025-06-06. On Rank Correlation Coefficients. https://arxiv.org/abs/2506.06056

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