← Search

Atticus Geiger

23 accepted papers

2026

Disentangling a Large Language Model’s Computation from its Chain-of-Thought

ICML 2026poster

Do the chains of thought (CoT) of reasoning Large Language Models (LLMs) reflect their internal computation? In this paper, we provide evidence of \textit{performative} CoT, where a model becomes strongly confident in its final answer, but continues generating excess tokens without revealing its int…

Cited by 0SourceScholar
2026

From Directions to Regions: Decomposing Activations in Language Models via Local Geometry

ICML 2026poster

Activation decomposition methods in language models are tightly coupled to geometric assumptions on how concepts are realized in activation space. Existing approaches search for individual global directions, implicitly assuming linear separability, which overlooks concepts with nonlinear or multi-di…

Cited by 0SourceScholar
2026

Language Models Use Lookbacks to Track Beliefs

ICLR 2026poster

How do language models (LMs) represent characters’ beliefs, especially when those beliefs may differ from reality? This question lies at the heart of understanding the Theory of Mind (ToM) capabilities of LMs. We analyze LMs' ability to reason about characters’ beliefs using causal mediation and abs…

Cited by 0SourceScholar
2026

Mixing Mechanisms: How Language Models Retrieve Bound Entities In-Context

ICLR 2026poster

A key component of in-context reasoning is the ability of language models (LMs) to bind entities for later retrieval. For example, an LM might represent *Ann loves pie* by binding *Ann* to *pie*, allowing it to later retrieve *Ann* when asked *Who loves pie?* Prior research on short lists of bound…

Cited by 0SourcecodeScholar
2025

AxBench: Steering LLMs? Even Simple Baselines Outperform Sparse Autoencoders

ICML 2025spotlight

Fine-grained steering of language model outputs is essential for safety and reliability. Prompting and finetuning are widely used to achieve these goals, but interpretability researchers have proposed a variety of representation-based techniques as well, including sparse autoencoders (SAEs), linear…

2025

Enhancing Automated Interpretability with Output-Centric Feature Descriptions

ACL 2025long

Automated interpretability pipelines generate natural language descriptions for the concepts represented by features in large language models (LLMs), such as “plants” or “the first word in a sentence”. These descriptions are derived using inputs that activate the feature, which may be a dimension or…

2025

HyperDAS: Towards Automating Mechanistic Interpretability with Hypernetworks

ICLR 2025poster

Mechanistic interpretability has made great strides in identifying neural network features (e.g., directions in hidden activation space) that mediate concepts (e.g., *the birth year of a Nobel laureate*) and enable predictable manipulation. Distributed alignment search (DAS) leverages supervision fr…

Cited by 0SourcePDFScholar
2025

MIB: A Mechanistic Interpretability Benchmark

ICML 2025poster

How can we know whether new mechanistic interpretability methods achieve real improvements? In pursuit of lasting evaluation standards, we propose MIB, a Mechanistic Interpretability Benchmark, with two tracks spanning four tasks and five models. MIB favors methods that precisely and concisely recov…

2024

Is This the Subspace You Are Looking for? An Interpretability Illusion for Subspace Activation Patching

ICLR 2024poster

Mechanistic interpretability aims to attribute high-level model behaviors to specific, interpretable learned features. It is hypothesized that these features manifest as directions or low-dimensional subspaces within activation space. Accordingly, recent studies have explored the identification and…

2024

RAVEL: Evaluating Interpretability Methods on Disentangling Language Model Representations

ACL 2024long

Individual neurons participate in the representation of multiple high-level concepts. To what extent can different interpretability methods successfully disentangle these roles? To help address this question, we introduce RAVEL (Resolving Attribute-Value Entanglements in Language Models), a dataset…

2024

ReFT: Representation Finetuning for Language Models

NeurIPS 2024spotlight

Parameter-efficient finetuning (PEFT) methods seek to adapt large neural models via updates to a small number of *weights*. However, much prior interpretability work has shown that *representations* encode rich semantic information, suggesting that editing representations might be a more powerful al…

2024

Updating CLIP to Prefer Descriptions Over Captions

EMNLP 2024main

Although CLIPScore is a powerful generic metric that captures the similarity between a text and an image, it fails to distinguish between a caption that is meant to complement the information in an image and a description that is meant to replace an image entirely, e.g., for accessibility. We addres…

2024

pyvene: A Library for Understanding and Improving PyTorch Models via Interventions

NAACL 2024system demonstrations

Interventions on model-internal states are fundamental operations in many areas of AI, including model editing, steering, robustness, and interpretability. To facilitate such research, we introduce pyvene, an open-source Python library that supports customizable interventions on a range of different…

2023

Causal Proxy Models for Concept-based Model Explanations

ICML 2023poster

Explainability methods for NLP systems encounter a version of the fundamental problem of causal inference: for a given ground-truth input text, we never truly observe the counterfactual texts necessary for isolating the causal effects of model representations on outputs. In response, many explainabi…

2023

Interpretability at Scale: Identifying Causal Mechanisms in Alpaca

NeurIPS 2023poster

Obtaining human-interpretable explanations of large, general-purpose language models is an urgent goal for AI safety. However, it is just as important that our interpretability methods are faithful to the causal dynamics underlying model behavior and able to robustly generalize to unseen inputs. Dis…

2023

ScoNe: Benchmarking Negation Reasoning in Language Models With Fine-Tuning and In-Context Learning

ACL 2023short

A number of recent benchmarks seek to assess how well models handle natural language negation. However, these benchmarks lack the controlled example paradigms that would allow us to infer whether a model had truly learned how negation morphemes semantically scope. To fill these analytical gaps, we p…

2022

CEBaB: Estimating the Causal Effects of Real-World Concepts on NLP Model Behavior

NeurIPS 2022accept

The increasing size and complexity of modern ML systems has improved their predictive capabilities but made their behavior harder to explain. Many techniques for model explanation have been developed in response, but we lack clear criteria for assessing these techniques. In this paper, we cast model…

Cited by 54SourcePDFScholar
2022

Causal Distillation for Language Models

NAACL 2022long

Distillation efforts have led to language models that are more compact and efficient without serious drops in performance. The standard approach to distillation trains a student model against two objectives: a task-specific objective (e.g., language modeling) and an imitation objective that encourag…

2022

Inducing Causal Structure for Interpretable Neural Networks

ICML 2022spotlight

In many areas, we have well-founded insights about causal structure that would be useful to bring into our trained models while still allowing them to learn in a data-driven fashion. To achieve this, we present the new method of interchange intervention training (IIT). In IIT, we (1) align variables…

2021

DynaSent: A Dynamic Benchmark for Sentiment Analysis

ACL 2021long

We introduce DynaSent (‘Dynamic Sentiment’), a new English-language benchmark task for ternary (positive/negative/neutral) sentiment analysis. DynaSent combines naturally occurring sentences with sentences created using the open-source Dynabench Platform, which facilities human-and-model-in-the-loop…

2021

Dynabench: Rethinking Benchmarking in NLP

NAACL 2021long

We introduce Dynabench, an open-source platform for dynamic dataset creation and model benchmarking. Dynabench runs in a web browser and supports human-and-model-in-the-loop dataset creation: annotators seek to create examples that a target model will misclassify, but that another person will not. I…

Cited by 471SourcePDFScholar