pith:QBDYUQWW
A Note on the Folding Test of Unimodality: limitation and improved alternative
The folding test of unimodality misclassifies certain multimodal mixtures as unimodal, but a double-folding version corrects the error.
arxiv:2605.13326 v1 · 2026-05-13 · stat.ME
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Claims
the folding-based criterion can systematically fail, misclassifying clearly multimodal distributions as unimodal. We fully characterize these failures for Dirac mixtures and extend the analysis to Gaussian mixtures. We then introduce a double-folding procedure that captures complementary information, leading to a new test, the Double Folding Test of Unimodality. It resolves the FTU failures and improves multimodality detection power in simulations.
That applying the folding operation twice captures complementary information about modality without introducing new biases or reducing detection power in non-mixture or other distribution settings.
The Double Folding Test of Unimodality resolves systematic failures of the original FTU on Dirac and Gaussian mixtures and enhances multimodality detection.
References
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| First computed | 2026-05-18T02:44:48.616490Z |
|---|---|
| Builder | pith-number-builder-2026-05-17-v1 |
| Signature | Pith Ed25519
(pith-v1-2026-05) · public key |
| Schema | pith-number/v1.0 |
Canonical hash
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curl -sH 'Accept: application/ld+json' https://pith.science/pith/QBDYUQWWCJV4ZGSYN5ZRLTF2PN \
| jq -c '.canonical_record' \
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Canonical record JSON
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