activity
20242026
collaborators

5 papers

math.ST2026

A Frequency-Domain approach to detect nonstationarity in dependent data

Mohamedou Ould Haye, Anne Philippe

Distinguishing long memory behaviour from nonstationarity can be very difficult as in both cases the sample autocovariance function decays very slowly. Available stationarity tests…

math.ST2026

Irregularly observed long-memory Levy-driven moving average processes

Mohamedou Ould Haye, Anne Philippe

We study long-memory continuous-time moving-average processes driven by a Levy process and observed at random renewal times. The sampling scheme introduces an additional source of…

math.ST2026

From nonstationarity to stationarity via noise: discrete Fourier transforms and sample mean asymptotics for testing

Mohamedou Ould Haye, Anne Philippe

We study the asymptotic behaviour of different statistics for time series exhibiting long memory and nonstationarity. For processes with memory parameter , we deriv…

stat.ME2025

A Frequency-Domain NonStationarity Test for dependent data

Mohamedou Ould Haye, Anne Philippe

Distinguishing long-memory behaviour from nonstationarity is challenging, as both produce slowly decaying sample autocovariances. Existing stationarity tests either fail to account…

math.ST2024

Asymptotics for irregularly observed long memory processes

Mohamedou Ould-Haye, Anne Philippe

We study the effect of observing a stationary process at irregular time points via a renewal process. We establish a sharp difference in the asymptotic behaviour of the self-normal…