activity
20242026
collaborators

6 papers

math.PR2026

Weak error approximation for rough and Gaussian mean-reverting stochastic volatility models

Aurélien Alfonsi, Ahmed Kebaier

For a class of stochastic models with Gaussian and rough mean-reverting volatility that embeds the genuine rough Stein-Stein model, we study the weak approximation rate when using…

q-fin.CP2026

How can the dual martingale help solving the primal optimal stopping problem?

Aurélien Alfonsi, Ahmed Kebaier, Jérôme Lelong

Motivated by recent results on the dual formulation of optimal stopping problems, we investigate in this short paper how the knowledge of an approximating dual martingale can impro…

q-fin.RM2026

Credit Spreads' Term Structure: Stochastic Modeling with CIR++ Intensity

Mohamed Ben Alaya, Ahmed Kebaier, Djibril Sarr

This paper introduces a novel stochastic model for credit spreads. The stochastic approach leverages the diffusion of default intensities via a CIR++ model and is formulated within…

math.PR2025

Local asymptotic properties for the growth rate of a jump-type CIR process

Mohamed Ben Alaya, Ahmed Kebaier, Gyula Pap +1

In this paper, we consider a one-dimensional jump-type Cox-Ingersoll-Ross process driven by a Brownian motion and a subordinator, whose growth rate is an unknown parameter. Conside…

q-fin.MF2024

A pure dual approach for hedging Bermudan options

Aurélien Alfonsi, Ahmed Kebaier, Jérôme Lelong

This paper develops a new dual approach to compute the hedging portfolio of a Bermudan option and its initial value. It gives a "purely dual" algorithm following the spirit of Roge…

q-fin.ST2024

Deep Calibration of Interest Rates Model

Mohamed Ben Alaya, Ahmed Kebaier, Djibril Sarr

For any financial institution, it is essential to understand the behavior of interest rates. Despite the growing use of Deep Learning, for many reasons (expertise, ease of use, etc…