collaborators

6 papers

cs.LG2025

A Statistical Theory of Contrastive Pre-training and Multimodal Generative AI

Kazusato Oko, Licong Lin, Yuhang Cai +1

Multi-modal generative AI systems, such as those combining vision and language, rely on contrastive pre-training to learn representations across different modalities. While their p…

cs.CL2025

When Does Metadata Conditioning (NOT) Work for Language Model Pre-Training? A Study with Context-Free Grammars

Rei Higuchi, Ryotaro Kawata, Naoki Nishikawa +7

The ability to acquire latent semantics is one of the key properties that determines the performance of language models. One convenient approach to invoke this ability is to prepen…

cs.LG2025

Direct Distributional Optimization for Provable Alignment of Diffusion Models

Ryotaro Kawata, Kazusato Oko, Atsushi Nitanda +1

We introduce a novel alignment method for diffusion models from distribution optimization perspectives while providing rigorous convergence guarantees. We first formulate the probl…

cs.LG2024

Neural network learns low-dimensional polynomials with SGD near the information-theoretic limit

Jason D. Lee, Kazusato Oko, Taiji Suzuki +1

We study the problem of gradient descent learning of a single-index target function un…

cs.LG2024

Pretrained transformer efficiently learns low-dimensional target functions in-context

Kazusato Oko, Yujin Song, Taiji Suzuki +1

Transformers can efficiently learn in-context from example demonstrations. Most existing theoretical analyses studied the in-context learning (ICL) ability of transformers for line…

cs.LG2024

Flow matching achieves almost minimax optimal convergence

Kenji Fukumizu, Taiji Suzuki, Noboru Isobe +2

Flow matching (FM) has gained significant attention as a simulation-free generative model. Unlike diffusion models, which are based on stochastic differential equations, FM employs…