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20222026
most citedThe exact region and an inequality between Chatterjee's and Spearman's rank correlations

2 citations · 8 across the 11 of their papers we have counts for

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math.ST2026

The exact region determined by Spearman's rho and Gini's gamma

Jonathan Ansari, Marcus Rockel, Stefanie Steinmaßl

We determine the exact attainable region of Spearman's rho and Gini's gamma over all bivariate copulas, resolving the remaining pairwise exact-region problem among Spearman's rho,…

math.ST2026

The exact Spearman rho-footrule region via optimal transport with applications to finite rankings, mixability, and Chatterjee's rank correlation

Jonathan Ansari, Marcus Rockel

We solve the open problem of determining the maximal value of Spearman's rho when Spearman's footrule is prescribed, thereby completing the exact attainable region of these two qua…

math.ST2026

Dependence Measures via Adapted Optimal Transport: Stability and Rates of Convergence

Jonathan Ansari, Johannes Wiesel

Recently studied dependence measures, such as Chatterjee's rank correlation, that characterize both independence and perfect functional dependence, provide a powerful framework for…

math.ST2026

On a copula product characterizing independence and perfect functional dependence

Jonathan Ansari

Recently studied dependence measures take values in [0,1], where 0 characterizes independence of X and Y, and 1 characterizes perfect functional (not necessarily monotone) dependen…

math.ST2025★ 2 cited

The exact region and an inequality between Chatterjee's and Spearman's rank correlations

Jonathan Ansari, Marcus Rockel

The rank correlation ξ(X,Y), recently established by Sourav Chatterjee and already popular in the statistics literature, takes values in [0,1], where 0 characterizes independence o…

math.ST2024★ 2 cited

Comparison results for positive supermodular dependent Markov tree distributions

Jonathan Ansari, Moritz Ritter

Positive dependencies have been compared in the literature under rather strong assumptions such as equality of conditional distributions, exchangeability, or stationarity. We estab…

math.ST2023

Dependence properties of bivariate copula families

Jonathan Ansari, Marcus Rockel

Motivated by recently investigated results on dependence measures and robust risk models, this paper provides an overview of dependence properties of many well-known bivariate copu…

math.ST2023

Quantifying and estimating dependence via sensitivity of conditional distributions

Jonathan Ansari, Patrick B. Langthaler, Sebastian Fuchs +1

Recently established, directed dependence measures for pairs of random variables build upon the natural idea of comparing the conditional distributions of given w…

math.ST2022

A direct extension of Azadkia & Chatterjee's rank correlation to multi-response vectors

Jonathan Ansari, Sebastian Fuchs

Recently, Chatterjee (2023) recognized the lack of a direct generalization of his rank correlation in Azadkia and Chatterjee (2021) to a multi-dimensional response vector. As a…