Saved in:
Bibliographic Details
Main Authors: Li, Millicent, Arroyo, Alberto Mario Ceballos, Rogers, Giordano, Saphra, Naomi, Wallace, Byron C.
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2509.13316
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911681267892224
author Li, Millicent
Arroyo, Alberto Mario Ceballos
Rogers, Giordano
Saphra, Naomi
Wallace, Byron C.
author_facet Li, Millicent
Arroyo, Alberto Mario Ceballos
Rogers, Giordano
Saphra, Naomi
Wallace, Byron C.
contents Recent interpretability methods have proposed to translate LLM internal representations into natural language descriptions using a second verbalizer LLM. This is intended to illuminate how the target model represents and operates on inputs. But do such activation verbalization approaches actually provide privileged knowledge about the internal workings of the target model, or do they merely convey information about the inputs provided to it? We critically evaluate popular verbalization methods and datasets used in prior work and find that one can perform well on such benchmarks without access to target model internals, suggesting that these datasets are not ideal for evaluating verbalization methods. We then run controlled experiments which reveal that verbalizations often reflect the parametric knowledge of the verbalizer LLM that generated them, rather than the knowledge of the target LLM whose activations are decoded. Taken together, our results indicate a need for targeted benchmarks and experimental controls to rigorously assess whether verbalization methods provide meaningful insights into the operations of LLMs.
format Preprint
id arxiv_https___arxiv_org_abs_2509_13316
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Do Activation Verbalization Methods Convey Privileged Information?
Li, Millicent
Arroyo, Alberto Mario Ceballos
Rogers, Giordano
Saphra, Naomi
Wallace, Byron C.
Computation and Language
Machine Learning
Recent interpretability methods have proposed to translate LLM internal representations into natural language descriptions using a second verbalizer LLM. This is intended to illuminate how the target model represents and operates on inputs. But do such activation verbalization approaches actually provide privileged knowledge about the internal workings of the target model, or do they merely convey information about the inputs provided to it? We critically evaluate popular verbalization methods and datasets used in prior work and find that one can perform well on such benchmarks without access to target model internals, suggesting that these datasets are not ideal for evaluating verbalization methods. We then run controlled experiments which reveal that verbalizations often reflect the parametric knowledge of the verbalizer LLM that generated them, rather than the knowledge of the target LLM whose activations are decoded. Taken together, our results indicate a need for targeted benchmarks and experimental controls to rigorously assess whether verbalization methods provide meaningful insights into the operations of LLMs.
title Do Activation Verbalization Methods Convey Privileged Information?
topic Computation and Language
Machine Learning
url https://arxiv.org/abs/2509.13316