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arXiv Computation and Language By Alireza Bayat Makou, Jingcheng Niu, Subhabrata Dutta, Iryna Gurevych

Many Circuits, One Mechanism: Input Variation and Evaluation Granularity in Circuit Discovery

Read the original on arXiv Computation and Language →

The paper investigates whether structural differences in circuits discovered by circuit discovery methods reflect distinct mechanisms. By varying input-token frequency while keeping the task constant, the authors find that although circuits appear specialized by frequency structurally, functional and representational analyses reveal no reliable differences, a phenomenon they call phantom specialization. Across multiple models and tasks, structurally distinct circuits implement the same computation, with core shared subgraphs recovering most of the performance and interchangeable internal representations confirmed by causal interventions.

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv Computation and Language.

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