activity
20242026
collaborators

9 papers

math.ST2026

Network inference for SDEs with diverging dimension under small noise

Francesco Iafrate, Nakahiro Yoshida, Stefano M. Iacus

We consider inference for network stochastic differential equations in a small-noise, high-dimensional regime, where the diffusion coefficient vanishes with $\ep\to0$ while the net…

math.ST2026

Risk comparison theorems and application to deep learning of diffusion coefficients

Arnaud Gloter, Nakahiro Yoshida

We investigate the nonparametric estimation of the diffusion matrix in stochastic differential equations featuring multidimensional, strong mixing covariate processes. We propose a…

math.ST2025

Drift estimation for rough processes under small noise asymptotic : QMLE approach

Arnaud Gloter, Nakahiro Yoshida

We consider a process $X^\ve$ solution of a stochastic Volterra equation with an unknown parameter in the drift function. The Volterra kernel is singular near zero, exhib…

math.ST2025

Deep learning of point processes for modeling high-frequency data

Yoshihiro Gyotoku, Ioane Muni Toke, Nakahiro Yoshida

We investigate applications of deep neural networks to a point process having an intensity with mixing covariates processes as input. Our generic model includes Cox-type models and…

math.ST2025

Drift estimation for rough processes under small noise asymptotic : trajectory fitting method

Arnaud Gloter, Nakahiro Yoshida

We consider a process $X^\ve$ that solves a stochastic Volterra equation with an unknown parameter in the drift function. The Volterra kernel is singular, and includes as…

math.ST2024

Statistical inference for highly correlated stationary point processes and noisy bivariate Neyman-Scott processes

Takaaki Shiotani, Nakahiro Yoshida

Motivated by estimating the lead-lag relationships in high-frequency financial data, we propose noisy bivariate Neyman-Scott point processes with gamma kernels (NBNSP-G). NBNSP-G t…

math.PR2024

Asymptotic expansion of the drift estimator for the fractional Ornstein-Uhlenbeck process

Ciprian A. Tudor, Nakahiro Yoshida

We present an asymptotic expansion formula of an estimator for the drift coefficient of the fractional Ornstein-Uhlenbeck process. As the machinery, we apply the general expansion…

math.ST2024

Log-rank test with coarsened exact matching

Tomoya Baba, Nakahiro Yoshida

It is of special importance in the clinical trial to compare survival times between the treatment group and the control group. Propensity score methods with a logistic regression m…

math.ST2024

Quasi-likelihood analysis for adaptive estimation of a degenerate diffusion process

Arnaud Gloter, Nakahiro Yoshida

The adaptive quasi-likelihood analysis is developed for a degenerate diffusion process. Asymptotic normality and moment convergence are proved for the quasi-maximum likelihood esti…