A Superprocess-based Approach to Rough CIR Processes and Feller Random Measures
Abstract
Feller random measures generalize the Feller diffusion (the CIR process) by giving it memory. They arise as the scaling limits of nearly unstable Hawkes processes, and include the rough CIR process and its hyper-rough and discontinuous relatives. We show that every Feller random measure is the occupation measure of a Dawson--Watanabe superprocess whose spatial motion is a killed Lévy subordinator, integrated over the branching time. This is a continuum analogue of the Hawkes--Oakes cluster representation. It yields existence, stability in the parameters, and stochastic equations driven by an explicit noise. The structure of this noise depends on whether the kernel has an atom at the origin. Without an atom, the noise is a Brownian motion time-changed by the distribution function of the measure. This leads to a martingale characterization and to sharp results on densities and their Hölder regularity. With an atom, the noise is a compensated inverse-Gaussian process time-changed by the compensator of that distribution function, and the measure is purely atomic.
Related
- Exponential functionals of two random walks and stationary measures of discrete growth processes
- A superprocess model for eDNA transport in random river environment
- Random dynamical systems generated by rough differential equations driven by controlled rough paths
- Quadratic variations of rough generalized Hermite processes: hidden long memory and a universal Gaussian boundary field
- Nearly-minimax variance estimation under rough random design
BibTeX
@misc{zitkovic2026superprocessbased,
title = {{A Superprocess-based Approach to Rough CIR Processes and Feller Random Measures}},
author = {Gordan Žitković},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.05675},
eprint = {2610.05675},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.05675},
}
RIS
TY - UNPB
TI - A Superprocess-based Approach to Rough CIR Processes and Feller Random Measures
AU - Gordan Žitković
PY - 2026
DA - 2026/10/05
PB - arXiv
DO - 10.48550/arxiv.2610.05675
UR - https://arxiv.org/abs/2610.05675
AB - Feller random measures generalize the Feller diffusion (the CIR process) by giving it memory. They arise as the scaling limits of nearly unstable Hawkes processes, and include the rough CIR process and its hyper-rough and discontinuous relatives. We show that every Feller random measure is the occupation measure of a Dawson--Watanabe superprocess whose spatial motion is a killed Lévy subordinator, integrated over the branching time. This is a continuum analogue of the Hawkes--Oakes cluster representation. It yields existence, stability in the parameters, and stochastic equations driven by an explicit noise. The structure of this noise depends on whether the kernel has an atom at the origin. Without an atom, the noise is a Brownian motion time-changed by the distribution function of the measure. This leads to a martingale characterization and to sharp results on densities and their Hölder regularity. With an atom, the noise is a compensated inverse-Gaussian process time-changed by the compensator of that distribution function, and the measure is purely atomic.
ER -