Dictionary Learning Improves Patch-Free Circuit Discovery in Mechanistic Interpretability: A Case Study on Othello-GPT

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: He, Zhengfu, Ge, Xuyang, Tang, Qiong, Sun, Tianxiang, Cheng, Qinyuan, Qiu, Xipeng
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866910336007798784
author He, Zhengfu
Ge, Xuyang
Tang, Qiong
Sun, Tianxiang
Cheng, Qinyuan
Qiu, Xipeng
author_facet He, Zhengfu
Ge, Xuyang
Tang, Qiong
Sun, Tianxiang
Cheng, Qinyuan
Qiu, Xipeng
contents Sparse dictionary learning has been a rapidly growing technique in mechanistic interpretability to attack superposition and extract more human-understandable features from model activations. We ask a further question based on the extracted more monosemantic features: How do we recognize circuits connecting the enormous amount of dictionary features? We propose a circuit discovery framework alternative to activation patching. Our framework suffers less from out-of-distribution and proves to be more efficient in terms of asymptotic complexity. The basic unit in our framework is dictionary features decomposed from all modules writing to the residual stream, including embedding, attention output and MLP output. Starting from any logit, dictionary feature or attention score, we manage to trace down to lower-level dictionary features of all tokens and compute their contribution to these more interpretable and local model behaviors. We dig in a small transformer trained on a synthetic task named Othello and find a number of human-understandable fine-grained circuits inside of it.
format Preprint
id arxiv_https___arxiv_org_abs_2402_12201
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Dictionary Learning Improves Patch-Free Circuit Discovery in Mechanistic Interpretability: A Case Study on Othello-GPT
He, Zhengfu
Ge, Xuyang
Tang, Qiong
Sun, Tianxiang
Cheng, Qinyuan
Qiu, Xipeng
Machine Learning
Sparse dictionary learning has been a rapidly growing technique in mechanistic interpretability to attack superposition and extract more human-understandable features from model activations. We ask a further question based on the extracted more monosemantic features: How do we recognize circuits connecting the enormous amount of dictionary features? We propose a circuit discovery framework alternative to activation patching. Our framework suffers less from out-of-distribution and proves to be more efficient in terms of asymptotic complexity. The basic unit in our framework is dictionary features decomposed from all modules writing to the residual stream, including embedding, attention output and MLP output. Starting from any logit, dictionary feature or attention score, we manage to trace down to lower-level dictionary features of all tokens and compute their contribution to these more interpretable and local model behaviors. We dig in a small transformer trained on a synthetic task named Othello and find a number of human-understandable fine-grained circuits inside of it.
title Dictionary Learning Improves Patch-Free Circuit Discovery in Mechanistic Interpretability: A Case Study on Othello-GPT
topic Machine Learning
url https://arxiv.org/abs/2402.12201