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Xuechen Li

15 accepted papers

2023

AlpacaFarm: A Simulation Framework for Methods that Learn from Human Feedback

NeurIPS 2023spotlight

Large language models (LLMs) such as ChatGPT have seen widespread adoption due to their ability to follow user instructions well. Developing these LLMs involves a complex yet poorly understood workflow requiring training with human feedback. Replicating and understanding this instruction-following p…

Cited by 523SourcePDFScholar
2023

Exploring the Limits of Differentially Private Deep Learning with Group-wise Clipping

ICLR 2023poster

Differentially private deep learning has recently witnessed advances in computational efficiency and privacy-utility trade-off. We explore whether further improvements along the two axes are possible and provide affirmative answers leveraging two instantiations of \emph{group-wise clipping}. To red…

Cited by 52SourcePDFScholar
2023

Synthetic Text Generation with Differential Privacy: A Simple and Practical Recipe

ACL 2023long

Privacy concerns have attracted increasing attention in data-driven products due to the tendency of machine learning models to memorize sensitive training data. Generating synthetic versions of such data with a formal privacy guarantee, such as differential privacy (DP), provides a promising path to…

2022

Infinitely Deep Bayesian Neural Networks with Stochastic Differential Equations

AISTATS 2022poster

We perform scalable approximate inference in continuous-depth Bayesian neural networks. In this model class, uncertainty about separate weights in each layer gives hidden units that follow a stochastic differential equation. We demonstrate gradient-based stochastic variational inference in this infi…

Cited by 66SourcePDFScholar
2022

Large Language Models Can Be Strong Differentially Private Learners

ICLR 2022oral

Differentially Private (DP) learning has seen limited success for building large deep learning models of text, and straightforward attempts at applying Differentially Private Stochastic Gradient Descent (DP-SGD) to NLP tasks have resulted in large performance drops and high computational overhead. W…

2022

When Does Differentially Private Learning Not Suffer in High Dimensions?

NeurIPS 2022accept

Large pretrained models can be fine-tuned with differential privacy to achieve performance approaching that of non-private models. A common theme in these results is the surprising observation that high-dimensional models can achieve favorable privacy-utility trade-offs. This seemingly contradicts k…

2021

When does preconditioning help or hurt generalization?

ICLR 2021poster

While second order optimizers such as natural gradient descent (NGD) often speed up optimization, their effect on generalization has been called into question. This work presents a more nuanced view on how the \textit{implicit bias} of optimizers affects the comparison of generalization properties.…

Cited by 50SourcePDFScholar
2020

Scalable Gradients for Stochastic Differential Equations

AISTATS 2020poster

The adjoint sensitivity method scalably computes gradients of solutions to ordinary differential equations. We generalize this method to stochastic differential equations, allowing time-efficient and constant-memory computation of gradients with high-order adaptive solvers. Specifically, we derive a…

2019

Stochastic Runge-Kutta Accelerates Langevin Monte Carlo and Beyond

NeurIPS 2019spotlight

Sampling with Markov chain Monte Carlo methods typically amounts to discretizing some continuous-time dynamics with numerical integration. In this paper, we establish the convergence rate of sampling algorithms obtained by discretizing smooth It\^o diffusions exhibiting fast $2$-Wasserstein contract…

2018

Isolating Sources of Disentanglement in Variational Autoencoders

NeurIPS 2018oral

We decompose the evidence lower bound to show the existence of a term measuring the total correlation between latent variables. We use this to motivate the beta-TCVAE (Total Correlation Variational Autoencoder) algorithm, a refinement and plug-in replacement of the beta-VAE for learning disentangled…