Linear probes can mistake rich nonlinear features for linear representations

Three diagnostics show that accurate decoding does not establish that a factor dominates a model’s representational geometry.

Academic
Nadir Kutluozen · Christian Internò · David Klindt

Cold Spring Harbor Laboratory · Bielefeld University

Research Digest··3 min read
Kutluozen, Internò and Klindt test a common inference in representation learning: that a factor decoded accurately by a linear probe must form a major axis of the representation.

The authors formalized a strict “linear world model” as a representation whose dominant variance is an affine function of known latent factors.

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