activity
20232026
collaborators

8 papers

math.OC2026

A proximal gradient method with adaptive backtracking for weakly smooth multiobjective optimization

Yuki Miyazaki, Masaru Ito, Shotaro Yagishita

In this paper, we propose a proximal gradient method with adaptive linesearch for multiobjective optimization problems whose objective functions are weakly smooth, i.e., they have…

math.OC2025

Simple linesearch-free first-order methods for nonconvex optimization

Shotaro Yagishita, Masaru Ito

This paper presents an auto-conditioned proximal gradient method for nonconvex optimization. The method determines the stepsize using an estimation of local curvature and does not…

math.OC2025

Convergence of linesearch-based generalized conditional gradient methods without smoothness assumptions

Shotaro Yagishita

The generalized conditional gradient method is a popular algorithm for solving composite problems whose objective function is the sum of a smooth function and a nonsmooth convex fu…

math.OC2025

Proximal gradient-type method with generalized distance and convergence analysis without global descent lemma

Shotaro Yagishita, Masaru Ito

We consider solving nonconvex composite optimization problems in which the sum of a smooth function and a nonsmooth function is minimized. Many of convergence analyses of proximal…

q-fin.MF2024

Optimal reinsurance and investment via stochastic projected gradient method based on Malliavin calculus

Yuta Otsuki, Shotaro Yagishita

This paper proposes a new approach using the stochastic projected gradient method and Malliavin calculus for optimal reinsurance and investment strategies. Unlike traditional metho…

stat.CO2024

Fast algorithm for sparse least trimmed squares via trimmed-regularized reformulation

Shotaro Yagishita

The least trimmed squares (LTS) is a reasonable formulation of robust regression whereas it suffers from high computational cost due to the nonconvexity and nonsmoothness of its ob…