Was the paired digital-twin test weak, or was its statistic?
research/free-robustpaired
Was the paired twin test weak, or was its statistic? Stylised pendulum, Student-t noise: the mean squared residual has power ~0.1 at a 10% Coulomb error up to n = 400, while median, trimmed, absolute and Huber statistics reach 0.94–1.00 from n = 50; Gaussian noise barely cares.
What it found
Follow-up to free-c2stpower, where a paired error test stalled at 0.09–0.20 power for a 10% Coulomb-friction error under Student-t(3) sensor noise. On the same stylised pendulum, the mean squared residual again has power 0.06–0.10 at every n up to 400, while a median, a 20%-trimmed mean, a mean absolute or a Huber statistic reaches 0.94–1.00 from n = 50 (400 null and 400 test replicates per cell). Under Gaussian noise the choice barely matters. Stylised; one seed per noise kind; not a claim about a physical system.
A figure from its own output
Paper, code and results
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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.