collaborators

5 papers

math.ST2026

The W-footrule coefficient: A copula-based measure of countermonotonicity

Enrique de Amo, David García-Fernández, Manuel Úbeda-Flores

We introduce the -footrule coefficient , a copula-based coefficient of negative association defined as the -distance to the countermonotonic copula . We prove that…

math.ST2026

Directional footrule-coefficients

Enrique de Amo, David García-Fernández, Manuel Úbeda-Flores

Rank-based dependence measures such as Spearman's footrule are robust and invariant, but they often fail to capture directional or asymmetric dependence in multivariate settings. T…

math.ST2025

Directional -coefficients

Enrique de Amo, David García-Fernández, Manuel Úbeda-Flores

In this paper we obtain advances for the concept of directional -coefficients, originally defined for the trivariate case in [Nelsen, R.B., Úbeda-Flores, M. (2011). Directiona…

math.ST2025

Total positivity and dependence of order statistics

Enrique de Amo, José Juan Quesada-Molina, Manuel Úbeda-Flores

In this comprehensive study, we delve deeply into the concept of multivariate total positivity, defining it in accordance with a direction. We rigorously explore numerous salient p…

math.ST2025

Modeling directional monotonicity with copulas

Enrique de Amo, David García-Fernández, José Juan Quesada-Molina +1

The purpose of this paper is to characterize the concept of monotonicity according to a direction related to a set of n random variables in terms of its associated n-copula C. We s…