activity
20232026
collaborators

11 papers

cs.LG2026

Understanding LLM Quantization through Activation-Guided Compensation and Orthogonal Residuals

Yamato Narita, Issei Sato

Post-training weight-activation quantization reduces the memory and inference costs of large language models, but aggressive W4A4 quantization remains difficult because activation…

cs.CL2026

Max-pooling Network Revisited: Analyzing the Role of Semantic Probability in Multiple Instance Learning for Hallucination Detection

Shota Fujikawa, Issei Sato

Hallucination detection has become increasingly important for improving the reliability of large language models (LLMs). Recently, hybrid approaches such as HaMI, which combine sem…

cs.LG2026

Power Distribution Bridges Sampling, Self-Reward RL, and Self-Distillation

Akiyoshi Tomihari, Issei Sato

Recent analyses question whether reinforcement learning (RL) is responsible for strong reasoning in large language models (LLMs). At the same time, distillation and inference-time…

cs.LG2026

Understanding Scattered Forest Search: A Version-Space Perspective on Multi-Turn Program Correction

Yuto Tanaka, Issei Sato

In multi-turn program correction, the state-of-the-art method Scattered Forest Search (SFS) has been proposed, employing Monte Carlo Tree Search (MCTS) with carefully crafted initi…

cs.AI2025

A Formal Comparison Between Chain of Thought and Latent Thought

Kevin Xu, Issei Sato

Chain of thought (CoT) elicits reasoning in large language models by explicitly generating intermediate tokens. In contrast, latent thought reasoning operates directly in the conti…

cs.LG2025

To CoT or To Loop? A Formal Comparison Between Chain-of-Thought and Looped Transformers

Kevin Xu, Issei Sato

Chain-of-Thought (CoT) and Looped Transformers have been shown to empirically improve performance on reasoning tasks and to theoretically enhance expressivity by recursively increa…

cs.LG2025

Gradient Heterogeneity Complements Hessian Heterogeneity in Transformer Optimization

Akiyoshi Tomihari, Issei Sato

Transformers are difficult to optimize with stochastic gradient descent (SGD) and largely rely on adaptive optimizers such as Adam. Despite extensive efforts, the mechanisms behind…

cs.CL2024

Rethinking Associative Memory Mechanism in Induction Head

Shuo Wang, Issei Sato

Induction head mechanism is a part of the computational circuits for in-context learning (ICL) that enable large language models (LLMs) to adapt to new tasks without fine-tuning. M…

cs.LG2024

On Expressive Power of Looped Transformers: Theoretical Analysis and Enhancement via Timestep Encoding

Kevin Xu, Issei Sato

Looped Transformers provide advantages in parameter efficiency, computational capabilities, and generalization for reasoning tasks. However, their expressive power regarding functi…

cs.LG2024

Understanding Linear Probing then Fine-tuning Language Models from NTK Perspective

Akiyoshi Tomihari, Issei Sato

The two-stage fine-tuning (FT) method, linear probing (LP) then fine-tuning (LP-FT), outperforms linear probing and FT alone. This holds true for both in-distribution (ID) and out-…

cs.CV2023

Understanding Parameter Saliency via Extreme Value Theory

Shuo Wang, Issei Sato

Deep neural networks are being increasingly implemented throughout society in recent years. It is useful to identify which parameters trigger misclassification in diagnosing undesi…