← Search

Jan Leike

14 accepted papers

2026

Bits That Count: Quantifying and Predicting Capabilities of Language Models

ICML 2026poster

What and how do language models learn during training? When does learning elicit \textit{existing} knowledge, and when does it primarily teach \textit{new} capabilities? We find that the amount of generalizable information language models learn during training predicts the origins of their emergent …

Cited by 0SourceScholar
2026

Constitutional Classifiers++: Production-Grade Defenses against Universal Jailbreaks

ICLR 2026poster

We introduce enhanced Constitutional Classifiers that deliver production-grade jailbreak robustness with dramatically reduced computational costs and refusal rates compared to previous-generation defenses. We first identify vulnerabilities in existing systems that evaluate model outputs without rega…

Cited by 0SourceScholar
2025

Quantifying Elicitation of Latent Capabilities in Language Models

NeurIPS 2025poster

Large language models often possess latent capabilities that lie dormant unless explicitly elicited, or surfaced, through fine-tuning or prompt engineering. Predicting, assessing, and understanding these latent capabilities pose significant challenges in the development of effective, safe AI systems…

Cited by 0SourceScholar
2025

Scaling and evaluating sparse autoencoders

ICLR 2025oral

Sparse autoencoders provide a promising unsupervised approach for extracting interpretable features from a language model by reconstructing activations from a sparse bottleneck layer. Since language models learn many concepts, autoencoders need to be very large to recover all relevant features. Howe…

2024

Let's Verify Step by Step

ICLR 2024poster

In recent years, large language models have greatly improved in their ability to perform complex multi-step reasoning. However, even state-of-the-art models still regularly produce logical mistakes. To train more reliable models, we can turn either to outcome supervision, which provides feedback for…

2024

Weak-to-Strong Generalization: Eliciting Strong Capabilities With Weak Supervision

ICML 2024oral

Widely used alignment techniques, such as reinforcement learning from human feedback (RLHF), rely on the ability of humans to supervise model behavior---for example, to evaluate whether a model faithfully followed instructions or generated safe outputs. However, future superhuman models will behave…

Cited by 260SourcePDFScholar
2022

Training language models to follow instructions with human feedback

NeurIPS 2022accept

Making language models bigger does not inherently make them better at following a user's intent. For example, large language models can generate outputs that are untruthful, toxic, or simply not helpful to the user. In other words, these models are not aligned with their users. In this paper, we sho…

2021

Quantifying Differences in Reward Functions

ICLR 2021spotlight

For many tasks, the reward function is inaccessible to introspection or too complex to be specified procedurally, and must instead be learned from user data. Prior work has evaluated learned reward functions by evaluating policies optimized for the learned reward. However, this method cannot disting…

2020

Learning Human Objectives by Evaluating Hypothetical Behavior

ICML 2020poster

We seek to align agent behavior with a user’s objectives in a reinforcement learning setting with unknown dynamics, an unknown reward function, and unknown unsafe states. The user knows the rewards and unsafe states, but querying the user is expensive. We propose an algorithm that safely and efficie…

Cited by 95SourcePDFScholar
2019

Learning to Understand Goal Specifications by Modelling Reward

ICLR 2019poster

Recent work has shown that deep reinforcement-learning agents can learn to follow language-like instructions from infrequent environment rewards. However, this places on environment designers the onus of designing language-conditional reward functions which may not be easily or tractably implemented…

Cited by 175SourcePDFScholar
2018

Reward learning from human preferences and demonstrations in Atari

NeurIPS 2018poster

To solve complex real-world problems with reinforcement learning, we cannot rely on manually specified reward functions. Instead, we need humans to communicate an objective to the agent directly. In this work, we combine two approaches to this problem: learning from expert demonstrations and learnin…

Cited by 504SourcePDFScholar
2017

Deep Reinforcement Learning from Human Preferences

NeurIPS 2017poster

For sophisticated reinforcement learning (RL) systems to interact usefully with real-world environments, we need to communicate complex goals to these systems. In this work, we explore goals defined in terms of (non-expert) human preferences between pairs of trajectory segments. Our approach separat…

Cited by 4197SourcePDFScholar