Leyang Hu 胡乐阳

PhD Student in Computer Science, Brown University

I am a PhD student in Computer Science at Brown University, advised by Prof. Randall Balestriero. My work connects the theory and practice of deep learning: theory guides practice, and practice inspires new theory.

Concretely, that runs in two directions.

News

Selected Publications

The complete and most current list is on Google Scholar.

  1. TAG-DS 2026

    Learning by Reconstruction is an Ill-Defined Prior for Perception: A Level Set View

    Leyang Hu, Matteo Gamba, Akshay Ghandikota, Akash Nagaraj, Randall Balestriero

    Encoders with identical reconstruction loss span 4%–74% linear-probe accuracy, so reconstruction underdetermines representation quality — what separates them is optimization’s implicit bias.

  2. Under Review 2026

    Is SSL Ready for In-Domain Pretraining? A Cross-Dataset Benchmark and Analysis

    Sami BuGhanem, Leyang Hu, Haodong Zhang, … Randall Balestriero

    A benchmark of six modern SSL methods across 41 image datasets, showing that modern SSL can be competitive with supervised learning for limited-data in-domain pretraining.

  3. NeurIPS 2025

    Curvature Tuning: Provable Training-Free Model Steering From a Single Parameter

    Leyang Hu, Matteo Gamba, Randall Balestriero

    Fine-tuning that updates activation functions instead of weights, provably reshaping decision boundaries — 10.20% higher downstream accuracy than LoRA with under 60% of the parameters.

  4. Preprint 2025

    Next Token Perception Score: Analytical Assessment of Your LLM Perception Skills

    Yu-Ang Cheng, Leyang Hu, Hai Huang, Randall Balestriero

    An analytical score for how well autoregressive pretraining features align with a downstream task, tracking linear-probe accuracy across 12 datasets and eight LLMs.

  5. ICML 2025

    Revolve: Optimizing AI Systems by Tracking Response Evolution in Textual Optimization

    Peiyan Zhang, Haibo Jin, Leyang Hu, … Haohan Wang

    LLM self-refinement that tracks how responses evolve across iterations, using discrete second-order differences for more stable textual optimization.

  6. Preprint 2024

    DROJ: A Prompt-Driven Attack Against Large Language Models

    Leyang Hu, Boran Wang

    An embedding-level jailbreak that optimizes adversarial prompts directly, reaching 98.46% attack success on AdvBench with Llama 2 7B.