Float32-Induced Distortion in Activation Patching: Precision Floors and Displacement-Dependent Endpoint-Curvature Error
Interaction-level activation patching is used to infer nonlinear cooperation in neural networks, but its numerical validity has not been systematically audited. In two pretrained checkpoints—GPT-2-medium and Pythia-410M, audited on one CUDA backend with a single templated cloze task family—we identified two independent...