LightNews
shiqianma.bsky.social
Shiqian Ma
@shiqianma.bsky.social
120 followers 94 following 3 posts

Professor at Rice University. Optimization and machine learning.

Videos
Engineering 42%
Computer science 30%
Posts Media Videos Starter Packs

shiqianma.bsky.social
Shiqian Ma @shiqianma.bsky.social · Feb 21
Two papers on bilevel optimization are published in JMLR. “Efficiently Escaping Saddle Points in Bilevel Optimization” and “Riemannian Bilevel Optimization” www.jmlr.org/papers/v26/2... www.jmlr.org/papers/v26/2...
Efficiently Escaping Saddle Points in Bilevel Optimization
www.jmlr.org
6

shiqianma.bsky.social
Shiqian Ma @shiqianma.bsky.social · Feb 21
Our paper on tuning-free gradient method: “AdaBB: Adaptive Barzilai-Borwein Method for Convex Optimization” is accepted in Math of OR. arxiv.org/abs/2401.08024
AdaBB: Adaptive Barzilai-Borwein Method for Convex Optimization
In this paper, we propose AdaBB, an adaptive gradient method based on the Barzilai-Borwein stepsize. The algorithm is line-search-free and parameter-free, and essentially provides a convergent variant...
arxiv.org
5

Reposted by Shiqian Ma

krizna.bsky.social
Krishna Balasubramanian @krizna.bsky.social · Feb 12
We implement these oracles using heat-kernel truncation & Varadhan's asymptotics, linking our method to entropy-regularized proximal point method on Wasserstein spaces, in the latter case.

Joint work with Yunrui Guan and @shiqianma.bsky.social
1 1

Reposted by Shiqian Ma

krizna.bsky.social
Krishna Balasubramanian @krizna.bsky.social · Feb 12
New work on Riemannian Proximal Sampler, to sample on Riemannian manifolds:

arxiv.org/abs/2502.07265

Comes with high-accuracy (i.e., log(1/eps), where eps is tolerance) guarantees with exact and inexact oracles for Manifold Brownian Increments and Riemannian Heat-kernels
Riemannian Proximal Sampler for High-accuracy Sampling on Manifolds
We introduce the Riemannian Proximal Sampler, a method for sampling from densities defined on Riemannian manifolds. The performance of this sampler critically depends on two key oracles: the Manifold ...
arxiv.org
1 1 4

shiqianma.bsky.social
Shiqian Ma @shiqianma.bsky.social · Jan 14
Our paper Riemannian Bilevel Optimization is accepted in Journal of Machine Learning Research! arxiv.org/abs/2402.02019
Riemannian Bilevel Optimization
In this work, we consider the bilevel optimization problem on Riemannian manifolds. We inspect the calculation of the hypergradient of such problems on general manifolds and thus enable the utilizatio...
arxiv.org
2