activity
20242026
collaborators

5 papers

math.ST2026

Spectra of high-dimensional Spearman correlation matrices under scale-mixture dependence

Jean-Philippe Bouchaud, Pierre Bousseyroux, Tomas Espana +1

We study the asymptotic spectral properties of high-dimensional Spearman correlation matrices for scale-mixture data. We consider observations of the form $x_t=σ_t ξ_t \in \mathb…

math.PR2026

Another Marcenko-Pastur law for Kendall's tau

Pierre Bousseyroux, Tomas Espana, Matteo Smerlak

Bandeira et al. (2017) show that the eigenvalues of the Kendall correlation matrix of i.i.d. random vectors in are asymptotically distributed like $1/3 + (2/3)Y_…

math.PR2026

Random Matrices and U-Statistics

Florent Benaych-Georges, Tomas Espana

We introduce a family of coefficients based on U-statistics that generalize the notion of correlation and explore their properties in the large dimensional multivariate case, showi…

q-fin.TR2025

Reinforcement Learning in Queue-Reactive Models: Application to Optimal Execution

Tomas Espana, Yadh Hafsi, Fabrizio Lillo +1

We investigate the use of Reinforcement Learning for the optimal execution of meta-orders, where the objective is to execute incrementally large orders while minimizing implementat…

q-fin.ST2024

Kendall Correlation Coefficients for Portfolio Optimization

Tomas Espana, Victor Le Coz, Matteo Smerlak

Markowitz's optimal portfolio relies on the accurate estimation of correlations between asset returns, a difficult problem when the number of observations is not much larger than t…